Explanation

Oily gives vowel sound.

Explanation

Articles "A" and "AN" are used with some expressions.

For example:

Make a noise, give a warning, have a pain, have a great education etc.

Explanation

D gives consonant sound.

Explanation

Articles "A" and "AN" are used with some expressions.

For example:

Make a noise, give a warning, have a pain, have a great education etc.

Explanation

To show similarity ÷ A/An or The = proper noun.

Explanation

He is a vegetarian.

وہ ایک سبزی خور ہے۔

Explanation

Useful gives consonant sound.

Gold is a useful metal. 

Explanation

The committee appointed him caption.

کمیٹی نے اس کو کیپٹن منتخب کرلیا ہے۔ 

No article

Explanation

Let's have a tea ?.

A/An + verb = noun.

Explanation

A and An are used before one.