Adjective

"beautiful", "ugry", "blue"and "red" are adjectives.
An adjective word describes a noun.

At the end of Japanese adjective word must be "-i".

kirei : beautiful, clean
utsukushii : beautiful
minikui : ugry
aoi : blue
akai : red

hana : flower

Kono hana wa utsukushii. : this, flower , beautiful : This flower is beautiful.

utsukushikatta : utsukushii + katta(past) : was/were beautiful

Kono hana wa utsukushikatta.:This flower was beautiful.

Japanese adjective is put in front of a noun like in English.
And adjective itself can make a role of a complement as well.

boushi : hat/cap
bara : rose

aoi boushi : blue cap
akai bara : red rose

Kore wa aoi boushi desu. : this, blue, cap, is : This is a blue cap.
Kono boushi wa aoi. : this, cap , blue : This cap is blue.