Chinese grammar: Separable verb

"Separable verbs," called 离合词 (líhécí) in Chinese, get their name from their ability to "separate" into two parts (a verb part and an object part), with other words in between. Separable verbs are an important concept to master in Chinese, and are also the source of many beginner mistakes. Mastering separable verbs is an essential objective of the intermediate (B1) level learner of Chinese.

What they are 
Mandarin's separable verbs have a counterpart in English: phrasal verbs (also called two-word verbs). While the structure of English's phrasal verbs is different, the "separable" quality works in a very similar way. Take the phrasal verb "check out" for example:

Check out my new computer.
Check my new computer out.

Do you see what happened there? The verb "check out" can split into two parts, and other words can go in between those two parts. Separable verbs work much the same way in Chinese.

Let's look at a typical example in Chinese, using the verb 见面, meaning "to meet."

我们 明天 见面（wǒ men mínɡ tiān jiàn miàn） 。(no separating)
我们 昨天 见 了 面 (wǒ men zuó tiān jiàn le miàn )。(separated, 了 inserted)
我们 见 过 三 次 面(wǒ men jiàn ɡuò sān cì miàn ) 。(separated, 过, 三次 inserted)

Below we will introduce separable verbs in more detail, provide more examples, and also offer more specific cases of wher separable verbs can get tricky.

Why use them? 
Separable verbs are just one of those things you can't avoid. Many extremely common verbs, such as "to sleep" (睡觉) or "to meet" (见面) are separable verbs, and until you understand which verbs are separable verbs and how they work, you'll forever be making mistakes with these verbs, even in very basic sentences.

How to use them 
First, you need to understand the structure of separable verbs. Most separable verbs are a "Verb + Object" (the object is a noun) construct. One might wonder, then, why there needs to be a separate category called "separable verbs" instead of just thinking of them as a verb and an object. There are several reasons to think of them as special verbs:

Many separable verbs can't be easily translated into other languages in a way that makes both the verb and the object part clear. For example, 睡觉 (to sleep), 游泳 (to swim), or 结婚 (to get married). In these examples, it's just not easy to think of the objects as an object.

The relationship between the verb and the object in a separable verb pair is very close; adding the object to the verb is sort of the "default form" of the verb, even if the verb part can be used without the object.
Separable verbs are a source of frequent errors from learners of Chinese. No matter how you think of them, it's good to give these "words" or "phrases" extra attention to make your Chinese more natural.

The key to using separable verbs correctly is to remember that they are "Verb + Object" constructs. The verb alone must be treated as a verb, and the object cannot be treated as a verb. It's from this essential relationship that the following principles flow:

Separable verbs already have an object

Remember, these are "Verb + Object" constructs. So even when a verb like 见面 (to meet) seems like it can take an object, it can't (面 is already the object of 见 in this case), so you can't put an additional object after the verb. In cases like this, you usually need to use a prepositional phrase before the verb.

√我 想 跟 你 见面 (wǒ xiǎnɡ ɡēn nǐ jiàn miàn )。(the prepositional phrase, literally "with you," comes before the verb)
×我 想 见面 你(wǒ xiǎnɡ jiàn miàn nǐ ) 。(你 is an extra object; 面 is already the object)

Put aspectual particles 了, 着, 过 after the verb
见 了 面 (jiàn le miàn )
开 着 会 (kāi zhe huì )
见 过 面 (jiàn ɡuò miàn )
Note: unlike the particles 过 and 着, the particle 了 is especially tricky, and it can also appear after the object. So it can be correct in multiple places.

Put measure words after the verb
见 一 次 面 (次 is a verbal measure word)
见 个 面 (个 is a general measure word for nouns)

When reduplicating, only reduplicate the verb

Reduplication is a way to express the casual nature of a verb, or that it happened only briefly. When it comes to separable verbs, only the verb part reduplicates.

√见见面 (jiàn jiàn miàn)。 (the proper reduplication repeats only the verb 见)
×见面见面(jiàn miàn jiàn miàn ) (面 is the object; it should not be repeated.)
×见见面面(jiàn jiàn miàn miàn) (面 is the object; it should not be repeated.)