比【bǐ】

比 compares two things. A goes first, B goes after 比, and the adjective comes last with nothing in front of it.

很 is dropped

This is the mistake to watch. A 比 sentence has no 很, 非常 or 太. tā他Bǐ比wǒ我hěn很Gāo高 is wrong – the comparison already supplies the degree.

The degree goes after the adjective

How much taller, how much colder – all of it follows the adjective.

更 and 还 are allowed

These two are the exception, and they say B is already high.

The negative is 没有, not 不比

To say A is less than B, use 没有…那么.

不比 exists but denies the comparison rather than reversing it: 我不比他高 means "I'm no taller than him", which allows them to be equal.

With a verb

The verb comes before 比 and repeats after the adjective, or takes 得.