The words 帮 (bāng) and 帮忙 (bāngmáng) can both mean "help" in Chinese. However, they're used in slightly different ways and have different constructions. Because of that, how to use 帮 and 帮忙 correctly can be confusing at first.
The main difference to remember is that 帮 can always take an object, and 帮忙 can in one structure but not in another.
How to use 帮
帮 is a transitive verb. As mentioned above, that means that it can be used with an object. The basic structure for this is:
[noun] 帮 [noun]
The first noun is the subject of the sentence and the second is the object. So, the structure is equivalent to something like "the subject helps the object" in English. Let's have a look at some example sentences:
第一个名词是句子的主语，第二个是宾语。所以，句子结构有点类似于英语里的"the subject helps the object"。一起看看一些例句：
wǒ lái bāng nǐ ba.
Let me help you.
nǐ kěyǐ bāng wǒ yīxià ma?
Can you help me?
wǒ bù yào bāng tā.
I don't want to help him.
帮 can also be used in a slightly more complicated structure, with a verb or verb phrase. This can be used to talk about helping people to do things.
[noun] 帮 [noun] [verb]
Note that the [verb] in the structure above is actually a verb phrase. That means it can be a mini-sentence of its own, containing a verb and maybe an object.
Let's have a look at some examples for this structure:
wǒ bāng wǒ mèimei zuò zuo yè.
I help my little sister do her homework.
nǐ kěyǐ bāng wǒ zhǎo zhǎo wǒ de yàoshi ma?
Can you help me look for my keys?
tā měi tiān dū bāng wǒ gàn huó.
He helps me with my work every day.
Notice how the verb phrase can include an object of its own, almost making it a mini-sentence. This makes the 帮 structure quite easy to use, as you can combine it with other sentence patterns you know.
When 帮 means "for" and not "help"
A common use of 帮 in Chinese is to talk about actions that are done for other people. The structure is exactly the same as above, but it doesn't mean "help" in English. This use of 帮 isn't about people co-operating to do something together ("help"), it's about one person doing something on behalf of another ("for").
Let's have a look at some example sentences for this use of 帮:
nǐ qù yóujú de shíhou kěyǐ bāng wǒ jì zhège ma?
Could you post this for me when you go to the post office?
wǒ de mìshū chángcháng bāng wǒ ānpái kāihuì.
My secretary often arranges meetings for me.
bāng wǒ dǎkāi chuānghù ba!
Could you open the window for me?
tā zuótiān bāng wǒ xiūle zìxíngchē.
Yesterday she fixed my bike for me.
Sometimes it may be ambiguous as to whether 帮 means "for" or "help". In those situations you simply have to work from context.
How to use 帮忙
Unlike 帮, the word 帮忙 can be transitive (can take an object) or intransitive (can't have an object) depending on the structure it's used in. Let's have a look at these two structures separately.
When 帮忙 is intransitive
This is probably the simpler of the two 帮忙 structures. The structure is:
[noun] 帮忙 [verb]
The verb here could also be a verb phrase. The important thing to note with the structure above is that there's no space for an object. In other words, this structure is intransitive.
Let's have a look at some example sentences:
nǐ lái bāngmáng zuò fàn ba!
Come and help with the cooking!
qǐng nǐ bāngmáng kāi gè mén hǎo ma?
Would you please open the door for me?
wǒ xiě xìn qǐng nǐ bāngmáng.
I'm writing to ask you a favor.
When 帮忙 is transitive
You can use 帮忙 with an object in the structure below. In this structure, 帮忙 is a separable verb. That means that to add you extra information (such as an object) in between the two characters, rather than after them.
帮 [other stuff] 忙
"Other stuff" here includes the object for 帮忙 or any other information that you might want to attach to the verb. It all goes in between 帮 and 忙.
Let's have a look at some example sentences for this structure:
nǐ kěyǐ bāng wǒ yīgè máng ma?
Can you help me?
tā bāngle nǐ hěnduō máng.
He helped you a lot.
jǐngchá bāngle wǒmen yīgè dàmáng.
The police helped us a lot.
With this structure, the object can only be a pronoun; you can't put any other nouns in there as the object.
Translated from: ChineseBoost
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