About adj+n.

noun noun 叫復合名詞(Compound Noun)

例子:
Convenience shop (not convenient shop)
Flower Shop (not floral shop)


adjective noun係點用:

(1) 一般adjective
adjective 係放係noun的前面及Verb to be的後面
例子:
(Fat) man is your father. - (noun的前面)
He is (fat). - (Verb to be的後面)

(2)情態形容詞
This book is (interesting).
I was (bored) in .....
簡單說死物用 present particple (ING) 人用past particple (ED)

(3) 動作形容詞
The (frozen - 己冰凍) chicken is cheap.
The (burning - 燒梗) house is Aunt home.
簡單說形形動作(進行梗)用 present particple (ING), 動作(完成咗)用 past particple (ED)

if i were u, i rather read 001 than the others, ezi 2 understand~

you are right, adjective modifies noun.
e.g. expensive cars, careful driver, wonderful world. Usually adjective is placed before noun.
e.g. Tom never drives fast. He is a careful driver.
e.g. Tom bought an expensive car last week.

But, adjective may also place after verb-to-be when the verb-to-be functions as linking verb.
e.g. The car is expensive.
e.g. They are smart.
e.g. Tom is tall.

noun noun is compound noun. you can also use adjective to describe it.
e.g. 1: sports car (describe it with an adjective) = an expensive sports car

e.g. 2: position report = a detailed position report.

「noun+ noun」呢種形式係用黎形容一ｄ專有名詞，例如：Convenience Store－－－便利店。
「adjective+ noun」就係形容一ｄ一般既事物，例如：Beautiful girl－－－漂亮的女孩。