比 (bǐ) lets you compare two people or things. You can use it to
say that one person is taller than another, or that one cup of tea is hotter
than another.
Put 比 between the things you compare
A 比 B + adjective
Start with the person or thing you are describing. Put 比 before the person
or thing you compare it with, then put the adjective at the end.
The order matters. 姐姐比我高 says that your sister is taller. 我比姐姐高
says that you are taller.
To describe the same comparison from the other side, swap the two people
and use the opposite adjective. 姐姐比我高 and 我比姐姐矮 (‘I am shorter
than my older sister’) describe the same difference in height. You can do
the same with 贵 and 便宜 (‘expensive’ and ‘cheap’), 多 and 少 (‘more’ and
‘less’), or 大 and 小 (‘big’ and ‘small’).
Leave out 很 in this pattern
You may already know how to describe something with 很 (hěn), as in 这件衣服很贵
(‘This item of clothing is expensive’). In a basic 比 comparison, put the
adjective directly after the second thing. Do not carry 很 over into this
pattern.
You also do not need 是 before the adjective.
Make a comparison from two facts
Suppose today’s temperature is thirty degrees and yesterday’s was twenty.
You can compare the two days with 热 (‘hot’).
Two separate descriptions do not always tell you which thing has more of a
quality. If both cups of tea are hot, you still need to know which is hotter
before choosing the order of your 比 sentence.
For comparisons involving ‘twice as much’ or other multiples, see the
lesson on 倍 (bèi).