Expressing "when" with "shi"

By now you should now how to express "when" using 的时候 (de shíhou). But there's also a slightly shorter, more formal way to do it: simply use 时 (shí) all by itself. (No 的!)

Structure

Time + 时，Subj. ⋯⋯

As time words can appear before or after the subject, you can also place the "Time + 时" phrase after the subject.

考试时不要说话。Kǎoshì shí bùyào shuōhuà.Don't talk when you're taking a test.
我面试时经常会问这个问题。Wǒ miànshì shí jīngcháng huì wèn zhège wèntí.I often ask this question during job interviews.
会议结束时老板才来。Huìyì jiéshù shí lǎobǎn cái lái.The boss didn't show up until the meeting was over.
我生气时不想说话。Wǒ shēngqì shí bù xiǎng shuōhuà.I don't want to talk when I'm angry.
他们大学毕业时就分手了。Tāmen dàxué bìyè shí jiù fēnshǒu le.They broke up when they graduated from college.
飞机起飞时，他关了手机和电脑。Fēijī qǐfēi shí, tā guān le shǒujī hé diànnǎo.When the plane took off, he turned off his cell phone and computer.
他太太提出离婚时，他很惊讶。Tā tàitai tíchū líhūn shí, tā hěn jīngyà.He was very surprised when his wife asked for a divorce.
他去世时，他的孩子都不在身边。Tā qùshì shí, tā de háizi dōu bù zài shēnbiān.His children weren't with him when he passed away.
我们公司成立时只有三个人。Wǒmen gōngsī chénglì shí zhǐyǒu sān gè rén.There were only three people when this company was founded.
跟别人说话时不要玩手机。Gēn biérén shuōhuà shí bùyào wán shǒujī.Don't play with your cell phone when you're talking with other people.

There are also two great examples of this pattern in the poem 《远和近》 by Gu Cheng (顾城) below:

你
一会看我
一会看云
我觉得
你看我时很远
你看云时很近