The verbs 拿 (ná) and 带 (dài) can both mean "bring" or "take", so what is the difference between the two? In short, the difference between 拿 and 带 is:
拿 focuses on the action of carrying or picking up an object, particularly in one's hands.
带 focuses on bringing or taking things with you, i.e. having something whilst moving.
Comparing 拿 and 带 directly
The best way to get an idea of the difference between 拿 and 带 is probably to compare them in identical sentences.
Nǐ néng dài duōshǎo xínglǐ?
How much luggage are you allowed to take?
Nǐ néng ná duōshǎo xínglǐ?
How much luggage can you carry?
Here you can see that whilst 带 and 拿 can both mean ‘take', 带 simply expresses the act of moving with an object, whereas 拿 focuses on the physical act of carrying it.
拿 is used to talk about physically picking things up or carrying them. When 拿 is used, you can always think of things being moved in someone's hands.
Taking to and from with 拿
Depending on the direction of the action, 拿 is often translated into "bring" or "take" in English. Let's have a look at "take" first:
Tā cóng shūjià shàng ná xiàláile yī běn shū.
He took a book down from the bookshelf.
Nǐ yīnggāi ná dào qiántái qù ba.
You should take it to the front desk.
Bringing to and from with 拿
You can also use 拿 to talk about bringing things to or from places:
Nǐ kěyǐ ná diǎn chī de lái ma?
Could you bring some food?
Tā cóng jiālǐ ná láile yī píng hóngjiǔ.
He brought a bottle of red wine from home.
Getting or acquiring with 拿
As well as talking about physically moving things around, 拿 can also be used to talk about ‘getting' or ‘acquiring' things.
Wǒ ná dàole qiānzhèng jiù kěyǐ qù.
I can go once I've got my visa.
Wǒ huì zài jīchǎng guìtái ná jīpiào.
I'll pick my ticket up at the airport counter.
Taking to and from with 带
As with 拿, whether 带 is translated into ‘bring' or ‘take' in English is decided by the direction of the movement. Chinese uses 带 for both directions:
Nǐ dài zhège qù sòng gěi tāmen ba.
Take this and give it to them.
Wǒ bǎ zhège dài zǒu kěyǐ ma?
Is it alright if I take this with me?
Bringing to and from with 带
If the direction is towards the speaker, then 带 becomes ‘bring' rather than ‘take':
Wǒ mò dài zài shēnshang.
I haven't brought it with me.
Nǐ dài sǎnle ma?
Did you bring an umbrella?
带 can be used with abstract / intangible things
Finally, another difference between 拿 and 带 is that 带 can be used with abstract or intangible things, whereas this doesn't tend to be the case with 拿.
Have a look at some examples:
Tā dàizhe qíguài de yǎnshén kànzhe wǒ.
He looked at me strangely.
Tā shuōhuà shì dàizhe nóngzhòng dì měiguó kǒuyīn.
She spoke with a thick American accent.
Tā liǎn shàng dàizhe cànlàn de xiàoróng.
He had a beaming smile on his face.