There is a book on the desk.

Tsukue no ue ni hon ga arimasu. : There is a book on the desk.
tsukue : desk
ue : on, above, up
ni : at
...no ue ni : on ...
hon : book
aru : be-verb, exist
(nai, ari-masu, aru, aru-toki, are-ba, are, arou, atta)
Tsukue no ue ni hon ga arimasu. : desk, on, book, exist : There is a desk on the desk.

Mondai ga arimasu. : There is a problem.
mondai : problem , question,
Mondai ga arimasu. : problem, exist(is) : There is a problem.

Toshokan niwa takusan no hon ga arimasu.: There are many books in a library.
toshokan : library
niwa : at
takusan : many
takusan no hon : many books
Toshokan niwa takusan no hon ga arimasu. : library, at, many, book, exist(are): There are many books in a library.

Eat and drink

Watashi wa paatii de tabetari nondari shimashita.: I ate and drank at the party.
paatii : party
taberu : eat
(tabe-nai, tabe-masu, taberu, taberu-toki, tabere-ba, tabero, tabeyou, tabeta)
nomu : drink
(noma-nai, nomi-masu, nomu, nomu-toki, nome-ba, nome, nomou, nonda)
...dari...dari : (verb) and (verb) , this structure have a nuance that " do this and also do that".
nondari : euphonic change of "nomi" of "-masu pattern" +dari
suru : do
(shi-nai, shi-masu, suru, suru-toki, sure-ba, shiro, shiyou, shita)
shimasu : do (polite) : shi(-masu pattern of "suru")+masu
mashita : past type of "masu"
Watashi wa paatii de tabetari nondari shimashita : I, party, at eat, drink, do: I ate and drank at the party.

kaitari yondari : write and read
kaku : write
(kaka-nai, kaki-masu, kaku, kaku-toki, kake-ba, kake, kakou, kaita)
kaitari : kaki+tari
tari : same with "dari". It depends on the verb whether " dari " or " tari " should be used.
yomu : read
(yoma-nai, yomi-masu, yomu, yomu-toki, yome-ba, yome, yomou, yonda)

naitari warattari : cry and laugh
naku : cry
(naka-nai, naki-masu, naku, naku-toki, nake-ba , nake, nakou, naita)
naitari : "naki" of "naki-masu" with euphonic change + tari
warau : laugh
(warawa-nai, warai-masu, warau, warau-toki, warae-ba, warae, waraou, waratta)
warattari : warai+tari

She looked happy.

Kanojo wa shiawase soudatta.: She looked happy.
kanojo : she
shiawase : happy, happiness
souda : look, it looks, they say
soudatta : looked, it looked, the said

Kanojo wa shiawase soudatta : shi, happy, looked : She looked happy.

Kanojo wa shiawase souda : She looks happy.

Sengetsu kanojo ni attatoki, kanojo wa fushiawase soudatta.:When I saw her last month, she looked unhappy.
sengetsu : last month
ni : to, with
au : see, meet
(awa-nai, ai-masu, au, au-toki,ae-ba,aou,atta)
atta-toki : When (I) saw/met
fushiawase : unhappy
Sengetsu kanojo ni attatoki : last month,her,with,saw when : When (I) saw/met her

Would you mind opening the window?

Mado o aketemo yoroshii desuka. : Would you mind opening the window ?
mado : window
akeru : open
(ake-nai, ake-masu,akeru,akeru-toki,akereba,akero,akeyou,aketa)
yoroshii : good, ok
desuka : ?

mado o akeru : open the window

(verb(-masu pattern))-temo yoroshii. : verb-ing is good
(verb(-masu pattern))-temo yoroshii desuka. : Is it good (OK) verb-ing?

Mado o aketemo yoroshii desuka : window, opening, good , ? : Would you mind opening the window?

Denwa o karitemo yoroshii desuka : telephone, borrow, good,? : Can I use the telephone?
kariru : borrow, use something which is no mine
(kari-nai, kari-masu, kariru,kariru-toki,karre-ba,kariro,kariyou,karita)

okarisuru : very polite word of "kariru"
o : a prefix to make the word polite
suru : do
o+kariru+suru : okarisuru

Denwa o okarishitemo yoroshii desuka : May I use the telephone ?

In spite of "kariru",you can use "tsukau" as "use".
tsukau : use
(tsukawa-nai,tsukai-masu,tsukau,tsukau-toki,tsukae-ba,tsukae,tsukaou,tsukatta)
When "tsukau" is attached with "-temo", euphonic change is needed.

tsukattemo : tsukai-temo

Denwa o tsukattemo yoroshii desuka. : Can I use the telephone ?

suwaru : sit down
(suwara-nai,suwari-masu,suwaru,suwaru-toki,suware-ba,suware,suwarou,suwatta)
Suwattemo yoroshii desuka : Can I sit down?
suwattemo : suwari-temo

tatsu : stand up
(tata-nai,tachi-masu,tatsu,tatsu-toki,tate-ba,tate,tatou,tatta)
Tattemo yoroshii desuka : Can I stand up ?
tattemo : tachi-temo

Where are you from?

Dochira kara desuka . : Where are you from?
dochira : where
kara : from
desuka : is?
Dochira kara desuka : where,from,is? : Where are you from?

Dochira kara kimashitaka: Where did you come from?
kuru : come
(ko-nai,ki-masu,kuru,kuru-toki,kure-ba,koi,koyou,kita)
kimashita : came (past pattern of "ki-masu")
kimashita+ka : "ka" makes the word interrogative.
Dochira kara kimashitaka.: where, from, came? : Where did you come from?

Don't do it.

Suruna : Don't do it.
suru : do
(shi-nai,shi-masu,suru,suru-toki,sure-ba,shiro,shiyou,shita)
suru+na : don't do (imperative)
shi-nai + de : don't do (imperative)

PatternC of verb conjugation + "na" means negative imperative sentence.
And patternA of verb conjugation +"nai"+"de" means same.

Miruna : Don't look.
miru : see, look, watch
(mi-nai,mi-masu,miru,miru-toki,mire-ba,miro,miyou,mita)
miru+na : don't look,don't watch
mi-nai+de : don't look, don't watch

"+na" pattern is very strong phrase.
If you want to say more politely, "kudasai" should be added after "-nai+de" pattern.

Minaide kudasai. : Don't look please.
Shinaide kudasai : Don't do (it) please.

In the case that the object word is needed, the object word is put at top of the sentense.

Watashi o minaide kudasai. : me, don't look ,please : Don't look at me ,please.
Hon o yomanaide kudasai. : book , don't read,please : Don't read a book, please.

conjunction ; but

ga/shikashi / shikashinagara : but
demo / kedo : but

"shikashi" means "but".
In our usual conversation (colloquial),"demo" is usually used istead of "shikashi/ shikashinagara".
"shikashi" is rather offcial.

Tsurai kedo arukanakerebanaranai : It is hard but I have to walk.
Tsurai . Demo arukanakerebanaranai : It is hard. But I have to walk.
Tsurai . Kedo arukanakerebanaranai : It is hard. But I have to walk.
tsurai : hard
aruku : walk
(aruka-nai,aruki-masu,aruku,aruku-toki,aruke-ba,aruke,arukou,aruita)
-shinakerebanaranai : have to , must
arukanakerebanaranai : have to walk, must walk

"demo" is usually put at the begining but middle of the sentence.

"shikashi" and " shikashinagara" should be put at the begining of the sentence not in the middle.
"ga" can be put in the middle.

Watashi wa totemo tsukareteiru.Shikashi hatarakanakerebanaranai. : I'm very tired. But I have to work.
Watashi wa totemo tsukareteiru ga hatarakanakerebanaranai. : I'm very tired but I have to work.
totemo : very
tsukareteiru : be tired
hataraku : work
(hataraka-nai,hataraki-masu,hataraku,hataraku-toki,hatarake-ba,hatarake,hatarakou,hataraita)
hatarakanakerebanaranai: have to work / must work

conjunction ; and, or

We use ,in a sentence, conjunction words to connect word and word, sentence and sentence and so on.

1.noun and noun
to : and
ka / aruiwa: or
koohii to ocha : coffee and tea
koohii : coffee
ocha : tea
anata to watashi : you and I
anata ka watashi : you or I

2.sentence and sentence
soshite / sorede : and
ka / aruiwa : or
Anata ga kita. Soshite watashi wa itta: You came. And I went.
Anata ga itta. Aruiwa kare ga itta. : You went. Or he went.
iku: go
(ika-nai,iki-masu,iku,iku-toki,ike-ba,ike,ikou,itta)

3.verb and verb
In connecting verb and verb, the verb should be conjugated.
Itte miru : Go and see.
iku : go
(ika-nai,iki-masu,iku,iku-toki,ike-ba,ike,ikou,itta)
itte : euphonic change of "iki"(iki-masu)+te : iki -te : go and
Kaite yomu : write and read
kaku : write
(kaka-nai,kaki-masu,kaku,kaku-toki,kake-ba,kake,kakou,kaita)
kaite : euphonic change of "kaki"(kaki-masu)+te : kaki-te : write and

If you forgot to make euphonic change and say " kakite miru", it is not wrong but old Japanese which samurai used.

Totte nageru : Catch and throw
toru : catch
(tora-nai, tori-masu,toru,toru-toki,tore-ba,tore,torou,totta)
totte : tori+te : catch and
nageru : throw
(nage-nai,nage-masu,nageru,nageru-toki,nagere-ba,nagero,nageyou,nageta)

Nagete toru : Throw and catch
nagete : nage-te : catch and
(Above case, there is no euphonic change)

This is not what I ordered.

Kore wa watashi ga chuumonshita mono dewa arimasen. : This is not what I ordered.
kore : this
watashi : I
chuumon : order(noun)
suru : do
(shi-nai,shi-masu,suru,suru-toki,sure-ba,shi-ro,shiyou,shita)
chuumonsuru : order(verb)
mono : thing
arimasu : is / are
arimasen : is not / are not
...dewa arimasen : is not..../ are not....

Watashi ga chuumonshita : I ordered.
watashi ga chuumonshita mono : what I ordered, a thing which I ordered
Kore wa watashi ga chuumonshita mono dewa arimasen. : this,I,ordered,thing,not : This is not what I ordered.

How old are you?

Phrases below are asking your age.

Toshi wa ikutsu desuka.
toshi : year, age
ikutsu : how many, how old
desu : is
ka : makes the sentence interrogative with being attached at the end of the sentence
Toshi wa ikutsu desuka : age, how many, is ? : How old are you ?

Anata wa nansai desuka .
anata : you
nan : what
sai : years old
nansai : how old
Anata wa nansai desuka : you, how old, is ? : How old are you?

Anata no nenrei wa ikutsu desuka .
nenrei : age
Anata no nenrei wa ikutsu desuka. : your age, how many, is? : What is your age?

What is your name ?

In English , there are several phrases to ask your name ,like
What is your name?, May I have your name,please and so on.

All the phrases below are sentences which ask your name.

Anatano namae wa nan desuka ? : your ,name, what,is,? : What is your name?
no : makes possessive case, A no B : A's B
anata : you
anatano : your
namae : name
nan / nani : what
desu : is / are : "desu" makes the sentence end with affirmation.
ka : "?" : "ka" makes the sentence interrogative

Onamae wa ? : Your name?
o- : makes the word polite

Onamae wa nan to osshaimasuka . : May I have your name?
ossharu : say(polite)
(osshara-nai,osshari-masu,ossharu,ossharu-toki,osshareba,(osshare),(ossharou),osshatta)
onamae wa nan to osshaimasuka : name, what,say : May I have your name?

Dochirasama desuka. : Who are you?
dochira : which
sama / san : is usually attached to a name like "Mr" or "Mrs".
eg ; Tanaka sama : Mr/Ms Tanaka

Donata desuka. : Who are you?
donata: who(polite)

Dare desuka. : Who are you?
dare : who

Where are you going to stay?

Dochira ni taizai saremasuka? : Where are you going to stay?
dochira : which
ni : at
taizai : stay
sareru : do (polite and admiring to a person to talk to, "sareru" can not be used for a speaker)
(sare-nai,sare-masu,sareru,sareru-toki,sarere-ba,(sarero),(sareyou),sareta)

"Dochira" literally means "which".
You can think that "no hoteru" is omitted .
Dochira (no hoteru) ni taizai saremasuka?: Which hotel are you going to stay at ?
hoteru : hotel
no : is connecting "dochira" and a noun which comes after it.
dochira no hotel : which hotel

Dochira ni irasshaimasuka ? : Where are you going?
irassharu : go (polite and admiring to a person to talk to)
(irasshara-nai,irasshari-masu,irassharu,irassharu-toki,irasshare-ba,(irasshare),(irassharou),irasshatta)

Dochira ni osumai desuka? : Where are you living?/ Whre do you live?
osumai : to be living, live

"Dochira" used for asking a place is very polite word.

Below are examples in which "dochira" are used as just "which".
Dochira ga yoi desuka ? : Which is good?
yoi : good
Dochira ga suki desuka ? : Which do you like?
suki : like, love

If you could hear the word "dochira" in the conversation, you may know "dochira" is used for a place or just as "which" in the context of the conversation.

How long are you going to stay in Japan?

Donokurai Nippon ni taizai shimasuka . : How long are you going to stay in Japan?
donokurai / dorekurai : how long, how much, how many, how far
dono : literally means "which"
kurai : grade,degree,
Nippon / Nihon : Japan
ni : at, in, to
taizai : stay(noun)
taizai suru : stay (verb)
suru : do
(shi-nai,shi-masu,suru,suru-toki,sure-ba,shiro,shiyou,shita)

"donokurai" is used for asking quantity, distance,degree,grade and so on in an interrogative sentence.
To be precise, some other explanatory word should be added to "donokurai", but in our colloquial that kind of explanatory words are usually omitted.

In above case, "donokurai" is questioning period you stay(days/months / years).
So "Donokurai no nissuu" Nippon ni taizai shimasuka" is also correct.
nissuu : the number of days
no : in terms of
Donokurai (no nissuu) Nippon ni taizai shimasuka : how,in terms of days, Japan, in, stay, do you: How long are you going to stay in Japan?

Koko kara toshin made wa donokurai desuka : How far is it from here to downtown?
koko : hire
kara : from
toshin : downtown
made : to, upto
donokurai : how far, how much

Koko kara toshin made wa donokurai (no jikan) desuka : here, from, downtown, to , how far, is? : How far is it from here to downtown.
jikan : time

Koko kara toshin made wa donokurai (no jikan) kakarimasuka : How long will it take to get downtown from here?
kakaru : take(time)
(kakara-nai,kakari-masu,kakaru,kakaru-toki,kakare-ba,kakare,kakarou,kakatta)
Koko kara toshin made wa donokurai kakarimasuka : here,from,downtown,to,how long,take?: How long will it take to get downtown from here?

"donokurai no jikan " can be substituted for " donokurai jikan ga".
Koko kara toshin made wa donokurai jikan ga kakarimasuka : How long will it take to get downtown from here?

making passive voice

Kono hon wa ookuno hito ni yomareteimasu : This book is read by many people
kono : this
hon : book
ooi :(adjective) many, much,
ookuno: "ooku"is stem,"no" connects the adjective with noun
hito : person, people,human
ookuno hito : many people
ni : by
yomu : read
(yoma-nai,yomi-masu,yomu,yomu-toki,yome-ba,yome,yomou,yonda)
reru/rareru : is attached form a of verb-conjugation and makes it passive voice
yoma+reru : is read

Kono hon wa ookuno hito ni yomareru : this, book, many people, by , is read.:This book is read by many people.

shiteiru : literaly means "is / are doing". Sometimes "shiteiru" describes not only the action but also situation
When "shiteiru" attached to verb, the verb should be form b (-masu form).
And sometimes verb should be with euphonic change.

yomu +shiteiru : yomi+ -teiru : yondeiru : is reading

yomu+rareru+shiteiru : yomareteiru : is been read, is read

and , lastly, "masu" is attached and the sentense becomes polite.

yomareteiru+masu : yomareteimasu. : is read

Kono hon wa ookuno hito ni yomareteimasu : This book is read by many people.

For example, let us try with "miru(see)".

miru: see, look,watch
(mi-nai, mi-masu, miru, miru-toki, mire-ba, miro, miyou,mita)

miru+rareru : mirareru
mirareru+shiteiru : mirareteiru
mirareteiru : mirareteimasu.

Anata wa dareka ni mirareteimasu : You are watched by someone

dareka : someone
ni : by

About "verb conjugation"

A verb consists of a stem and auxiliary verb / particle.
A stem of a verb should be changed depending on its meaning in the sentense.
Basically "verbs" have 6 forms of conjugation.

a : Imperfective form (mizenkei) : to be attached with ,for example, negative auxiliary "nai"
b : Continuative form(ren'youkei) : to be attached with, for example,polite auxiliary " masu"
c : Terminal form (shuushikei) : to be used at the end of the sentense.plain form. dictionary form
d : Attributive form (rentaikei) : to be attached with mainly a noun,for example, "toki"(when)
e : Hypothetical form (kateikei) : to be used for conditional foms with " reba/ eba".
f : Imperative form (meireikei) : to be used to make verbs be commands.

It is not important to know grammatical terms mentioned above, but when you learn a verb, you'd better see all the conjugation forms of the verb.

I give you an instance the case of "kaku"(:write)
form a :kaka(stem): kaka-nai : do not write
form b : kaki(stem):kaki-masu : write (polite)
form c : kaku(stem):kaku :write(plain)
form d : kaku(stem):kaku-toki : write,when : when you write
form e : kake (stem): kake-ba : write,if : if you write
form f : kake(stem): kake : write : (You) Write.

Sometimes we can see additional form g.
form g : kakou : let's write.

Moreover, in the case of past tense, "ta" / "da" / "ita"/"datta" and etc would be attaced to form b,but you should learn them as another form h.

e.g.
kaku :write
(kaka-nai, kaki-masu, kaku,kaku-toki,kake-ba,kake,kakou,kaita)
miru : look, see
(mi-nai,mi-masu,miru,miru-toki,mire-ba,miro,miyou,mita)
yomu : read
(yoma-nai,yomi-masu,yomu,yomu-toki,yome-ba,yome,yomou,yonda)
hashiru : run
(hashira-nai,hashiri-masu,hashiru,hashiru-toki,hashire-ba,hashire,hashirou,hashitta)

I have to go.

Watashi wa ikanakerebanaranai. : I have to go.
watashi : I
iku : go
(ika-nai,iki-masu, iku,iku-toki,ike-ba, ike)
ika-nakerebanaranai : must go, have to go/ has to go
ika-kakerebaikenai : must go, have to go/ has to go

Watashi wa repooto wo kakanakerebanaranai : I have to write a report.
repooto : report
kaku : write
(kaka-nai, kaki-masu,kaku, kaku-toki, ka-keba,kake)
kaka-nakerebanaranai : must write, have to write / has to write
kaka-nakerebaikenai : must write, have to write / has to write

Watashi wa kodomotachi no mendou o minakerebanaranai : I have to take care of children.
kodomo : child
kodomotachi : children
mendou : matter
miru : look, see
(mi-nai, mi-masu, miru, miru-toki, mire-ba, mi-ro)
mendou o miru : take care of
mendou o mi-nakerebanaranai : must/have/has to take care of

Anata wa ni ji madeni shigoto o katazukenakerebanaranai : You must finish your work by 2 o'clock.
anata : you(single)
ni : two
ji : o'clock
madeni : by
shigoto : work, job, assignment,mission
katazukeru : finish
(katazuke-nai, katazuke-masu, katazukeru, katazukeru-toki, katazukere-ba, katazuke-ro)
katazuke-nakerebanaranai : must/have/has to finish
Japanese word order : you,two,o'clock,work,must finish : You must finish your work by two o'clock.