First, then, as soon as: 先…再, 一…就, 以后, 的时候

First … then: 先 … 然后 / 再

先 (xiān) = first, before the first verb. The next step starts with 然后 (ránhòu, then, after that), or has 再 (zài, then) before its verb. You can use both: 然后再.

• 我们先吃饭，然后去看电影。(Wǒmen xiān chī fàn, ránhòu qù kàn diànyǐng.)Let's eat first, then go and see a film.
• 你先洗手，再吃饭。(Nǐ xiān xǐshǒu, zài chī fàn.)Wash your hands first, then eat.

再 looks forward: it's for plans, instructions and suggestions. When you tell what already happened, 然后 is the safe choice: 我先去了银行，然后去了超市 (I went to the bank first, then the supermarket).

As soon as: 一 … 就

一 (yī) goes before the first verb, 就 (jiù) before the second. The subject of each part comes before 一 and 就. It means "as soon as", or, for habits, "every time".

• 他一喝酒就脸红。(Tā yì hē jiǔ jiù liǎn hóng.)Every time he drinks, his face goes red.
• 你一到北京就给我打电话吧。(Nǐ yí dào Běijīng jiù gěi wǒ dǎ diànhuà ba.)Call me as soon as you get to Beijing.

With two subjects: 我一到家，他就来了 (wǒ yí dào jiā, tā jiù lái le) = He came as soon as I got home. Remember the tone of 一 changes with the next syllable (Tone changes: 你好, 不 and 一).

After and before: 以后 and 以前

English says after class; Chinese says class after. 以后 (yǐhòu, after) and 以前 (yǐqián, before) come after the event:

• 下课以后，我们去喝咖啡吧。(Xiàkè yǐhòu, wǒmen qù hē kāfēi ba.)After class, let's go for a coffee.
• 睡觉以前，我喜欢看一会儿书。(Shuìjiào yǐqián, wǒ xǐhuan kàn yíhuìr shū.)Before bed, I like to read for a while.

The same works with a length of time: 三天以后 = three days later. The short forms 后 and 前 are common too: 饭后 (after meals), 睡觉前 (before bed). On their own, 以后 means "in future" and 以前 means "in the past" (了: a completed action).

When, while: 的时候

的时候 (de shíhou) also comes after the event: "the time of …".

• 我小的时候住在上海。(Wǒ xiǎo de shíhou zhù zài Shànghǎi.)When I was little, I lived in Shanghai.
• 吃饭的时候别看手机。(Chī fàn de shíhou bié kàn shǒujī.)Don't look at your phone while you're eating.

Common mistakes

• 以后下课，我们去吃饭。 → 下课以后，我们去吃饭。以后 comes after the event.
• 下课的以后 → 下课以后. 以后 and 以前 take no 的; only 时候 does.
• 什么时候我小，我住在上海。 → 我小的时候，我住在上海。什么时候 asks "when?"; for "when I was …" use 的时候.
• 我就一到家睡觉了。 → 我一到家就睡觉了。一 goes before the first verb, 就 before the second.
• 一我到家，就他来了。 → 我一到家，他就来了。Each subject comes before 一 or 就.