As adjective as grammar

1. A = B ( when two elements are the same )

Chris is as tall as his brother.
She was as white as a sheet.

2. A > < B ( when two elements are different ).

Her coffee is not as good as the coffee my mother makes.

3. When you compare two elements by using 'than'.

She makes fewer mistakes than you (do).
It was more expensive than I thought.
He is stronger than I expected.

4. When you compare three or more elements, use the superlative of adjectives and the ... in/of:

This is the oldest buidling in New York.
This is the best pizza (that) I have ever eaten.
This is the worst film (that) I have ever seen.