The Mandarin 把 (bǎ) Construction: Fronting the Object to Say What You Did To It

The principle: disposal

把 is often called the 'disposal' construction, and that label is the fastest way in. The sentence is about what the subject DID TO a specific object - moved it, changed it, finished it, put it somewhere. You front the object so the verb has room to express the result.

Compare the two orders:

我吃饭。 (Wǒ chī fàn.) - I eat (rice / a meal). Plain SVO, no disposal, no 把.
我把饭吃完了。 (Wǒ bǎ fàn chī wán le.) - I finished the (specific) meal. Disposal: here is what happened to the meal.

The basic pattern is:

Subject + 把 + (definite) Object + Verb + completion

The 'completion' slot is the heart of it. The verb cannot end the sentence bare. It needs something attached: 了, a resultative complement (完, 好, 对, 干净), a directional complement (起来, 出去, 下来), or an endpoint with 到 / 在 / 给 / 成.

Why the verb must be 'complete'

This is the single rule that breaks the most learner sentences. A bare verb after 把 is wrong.

我把书看。 (Wǒ bǎ shū kàn.) - WRONG. The verb 看 is bare; nothing was done to the book.
我把书看完了。 (Wǒ bǎ shū kàn wán le.) - RIGHT. I finished reading the book.

The logic: 把 announces 'here is the thing I disposed of', and then the listener is waiting to hear HOW it was disposed of. A bare verb leaves that promise unfulfilled. You have to land the result.

Acceptable ways to complete the verb:

了 (completion): 我把门关了。 (Wǒ bǎ mén guān le.) - I closed the door.
完 (finished): 我把作业做完了。 (Wǒ bǎ zuò yè zuò wán le.) - I finished the homework.
好 (done properly): 我把行李收好了。 (Wǒ bǎ xíng li shōu hǎo le.) - I packed the luggage (and it's done).
resultative complement: 我把衣服洗干净了。 (Wǒ bǎ yī fu xǐ gān jìng le.) - I washed the clothes clean.
directional complement: 他把书拿出来了。 (Tā bǎ shū ná chū lái le.) - He took the book out.

The thing you cannot do is stop on the bare verb. 我把衣服洗 (I did something to the clothes wash) is not a sentence.

The object must be specific

把 fronts a DEFINITE object - one the listener can identify. 'The book', 'this letter', 'my keys', 'it'. You do not use 把 for a brand-new, indefinite 'a book'.

我把那本书看完了。 (Wǒ bǎ nà běn shū kàn wán le.) - I finished THAT book. RIGHT.
我把一本书看完了。 (Wǒ bǎ yì běn shū kàn wán le.) - I finished A book. ODD / WRONG - the object is indefinite.

If the object is new and indefinite, use plain SVO instead: 我看完了一本书 (Wǒ kàn wán le yì běn shū.) - I finished a book. Save 把 for when both speaker and listener already know which object you mean. A bare noun in the 把 slot is read as definite anyway: 我把书看完了 means 'the book', not 'a book'.

Where negation and adverbs go: BEFORE 把

In plain sentences, negation sits right before the verb. In a 把 sentence, the verb is buried at the end behind the object, so negation and adverbs jump to the front and sit BEFORE 把, not before the verb.

我没把门关上。 (Wǒ méi bǎ mén guān shàng.) - I didn't close the door. RIGHT.
我把门没关上。 - WRONG. 没 cannot sit inside the construction next to the verb.
别把它扔了。 (Bié bǎ tā rēng le.) - Don't throw it away. (别 before 把.)
你别把这件事告诉他。 (Nǐ bié bǎ zhè jiàn shì gào su tā.) - Don't tell him about this.

Auxiliaries and time adverbs follow the same rule - they precede 把:

我想把这个问题解决。 (Wǒ xiǎng bǎ zhè ge wèn tí jiě jué.) - I want to solve this problem. (想 before 把.)
我已经把钱还给他了。 (Wǒ yǐ jīng bǎ qián huán gěi tā le.) - I've already paid him back. (已经 before 把.)
请先把手机关掉。 (Qǐng xiān bǎ shǒu jī guān diào.) - Please turn off your phone first. (先 before 把.)

Memory hook: everything that would normally hug the verb in a plain sentence migrates to the front of 把, because 把 has taken the verb hostage at the end of the clause.

When 把 is effectively required: O + V + 到 / 在 / 给 / 成

There is a class of sentences where you have no real choice but to use 把. When the verb carries an endpoint that says WHERE the object ends up, WHO receives it, or WHAT it becomes, plain SVO collapses and 把 becomes the natural - often the only - structure. These use 到, 在, 给, or 成 after the verb.

到 (to a destination): 请把书放到桌子上。 (Qǐng bǎ shū fàng dào zhuō zi shang.) - Please put the book onto the table.
在 (located at): 他把车停在门口。 (Tā bǎ chē tíng zài mén kǒu.) - He parked the car at the entrance.
给 (handed to a recipient): 我把钥匙给给他了 → in practice 我把钥匙交给他了。 (Wǒ bǎ yào shi jiāo gěi tā le.) - I handed the keys to him.
成 (changed into): 请把这句话翻译成英文。 (Qǐng bǎ zhè jù huà fān yì chéng yīng wén.) - Please translate this sentence into English.

Try saying 'put the book on the table' without 把 and you will struggle: 我放书在桌子上 is clumsy and substandard. The displacement and the result are exactly what 把 is built to carry, so this is where it earns its keep.

Worked examples

Six full sentences, broken down.

我把窗户打开了。 (Wǒ bǎ chuāng hu dǎ kāi le.) - I opened the window. 把 + definite object 窗户 + verb 打 + directional 开 + 了.
妈妈把饭做好了。 (Mā ma bǎ fàn zuò hǎo le.) - Mum has made the meal (and it's ready). Result complement 好 lands the disposal.
他没把作业写完。 (Tā méi bǎ zuò yè xiě wán.) - He didn't finish the homework. Negation 没 sits before 把; note no 了 after a 没 sentence.
请把垃圾扔到垃圾桶里。 (Qǐng bǎ lā jī rēng dào lā jī tǒng li.) - Please throw the rubbish into the bin. 到 + endpoint, the near-compulsory case.
我已经把邮件发给老板了。 (Wǒ yǐ jīng bǎ yóu jiàn fā gěi lǎo bǎn le.) - I've already sent the email to the boss. Adverb 已经 before 把; 给 marks the recipient.
别把这件事忘了。 (Bié bǎ zhè jiàn shì wàng le.) - Don't forget about this. Imperative negation 别 before 把.

Common mistakes

Bare verb after 把. 我把书看 is the classic error. The verb must carry a completion: 我把书看完了. If you cannot attach 了 / 完 / 好 / a complement / an endpoint, you probably should not be using 把 at all.
Negation inside the construction. 没 and 别 go BEFORE 把, never next to the buried verb. 我没把门关上, not 我把门没关上.
Indefinite object. 把 needs a definite object. 我把一本书看完了 is wrong; use plain SVO (我看完了一本书) or make the object definite (我把那本书看完了).
Using 把 for stative or perception verbs. Verbs that do not 'do something to' the object resist 把. You cannot say 我把她爱 (I dispose of her love) or 我把音乐听 - there is no disposal. 把 is for verbs that act on and change or move the object.
Forgetting the endpoint marker. With placement and transformation, do not drop 到 / 在 / 成. 我把书放桌子上 wants 放到: 我把书放到桌子上.
Over-using 把 in plain statements. 'I eat rice' is 我吃饭, not 我把饭吃. Reach for 把 only when there is a real result, displacement, or change to report.