Here's the answer:
“需要帮忙吗？”
(xū-yào bāng-máng ma?)
Watch a real native speaker say it:
Here's how it sounds in a textbook:
You could also say:
- nǐ xū-yào bāng-máng ma?
Fun fact: the hundreds of thousands of people learning Chinese with Memrise get this phrase correct 91.02% of the time!
