This article will look at three related but distinct words in Chinese: 碰, 碰见 and 碰上.
碰 is the simplest of the three words. It simply means "to touch" or "to hit" (in a non-aggressive sense).
Have a look at some example sentences:
tāmen pèngle pèng bēizi.
They clinked their glasses together.
Mind your head.
bié pèng wǒ!
Don't touch me!
tā tóu yī pèng zhěntou jiù shuìzhaole.
She was asleep the moment her head hit the pillow.
碰 is quite a versatile word, and can be used to describe various kinds of contact between two things.
Unlike 碰, 碰见 has quite a specific meaning. It means "to bump into", in the sense of unexpectedly meeting someone.
This is just a metaphorical extension of 碰, and is very similar to "bump into" in English.
wǒ zuótiān pèngjiàn tāle.
I bumped into him yesterday.
nǐ cāi wǒ jīntiān pèngjiàn shéi le!
Guess who I ran into today!
wǒ zuìjìn lǎo shì méi pèngjiàn nǐ.
I haven't bumped into you recently.
Just as 碰见 is an extension of 碰, you could say that 碰上 is an extension of 碰见.
Like 碰见, 碰上 can be used to talk about meeting someone unexpectedly:
wǒ yǐqián jīngcháng pèng shàng tā.
I used to bump into her all the time.
wǒ pèng shàngle yīgè lǎo péngyǒu.
I bumped into an old friend.
碰上 also has a further meaning, which is to encounter something other than a person. That sounds pretty weird, but it's actually just for situations like these:
kàn lái wǒmen yào pèng shàng yī chǎng bàofēngyǔ.
Looks like we're in for a storm.
wǒmen shéi dūhuì bùshí pèng shàng xiēxiǎo máfan.
We all encounter a few problems.
Translated from: chineseboost
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