The grammatical term 离合词 líhécí in Chinese refers to a group of verbs; they can be used as a single verb or can be separated and used as a verb + object phrase.
Take 上课 for example：
1.我每天上午九点上课。（I have class at 9 o’clock every morning.）
2.我每天上午九点上汉语课。（I have Chinese class at 9 o’clock every morning.）
In the first sentence, 上课 is used as a single verb, in the second sentence, 上课 is separated to 上 and 课，and becomes a verb + object phrase.
Because 上课 resembles the English verb + object phrase “have lesson” or “have class”, it’s not hard to understand what this separable verb is or how to use it. However, not every separable verb in Chinese has an equivalent verb + object phrase in English, which easily causes some Chinese learners to make mistakes.
Then, how shall we master this special Chinese language grammar?
Memorize the most commonly used Chinese separable verbs that don’t have equivalent verb + object phrases in English:
1. 帮忙 (help)
2. 道歉 (apologize)
3. 见面 (meet)
4. 跑步 (run)
5. 洗澡 (bath)
6. 散步 (walk)
7. 聊天 (chat)
8. 跳舞 (dance)
9. 结婚 (marry)
10. 离婚 (divorce)
11. 睡觉 (sleep)
12. 考试 (test)
13. 毕业 (graduate)
14. 吵架 (quarrel)
15. 游泳 (swim)
1. Chinese separable verbs can not be followed by objects.
Chinese separable verbs are all intransitive. Since a separable verb can be separated to a verb and an object, that means it has an object already.
He’s got troubles; I want to help him.
He bathes his dog every day.
I will meet you tomorrow.
2. When a separable verb is separated to a verb and an object, auxiliary word such as 了, 过, 着 are only allowed to be placed after the verb, not the object.
We chatted for a while yesterday evening.
He has been married before.
They are having a lesson.
3. When a separable verb is separated into a verb and an object, the measure words can only be placed after the verb, not the object.
I swim 3 times a week.
I sleep for 8 hours every day.
4. In Chinese, you can reduplicate verbs such as 看看，学习学习，to imply the brief duration of an action or to give the action a relaxed tone. However, when you reduplicate a separable verb, you only can reduplicate its verb part, not the object part.
To intermediate-level learners of Chinese Mandarin, the separable verb is an inevitable grammar point. Mastering its usage doesn’t seem difficult, but it takes time to use it naturally. From my point of view, if you can memorize the most commonly used ones and practice them as much as possible, sooner or later, you will be like every native Chinese speaker and won’t feel they are “special verbs” any more.