What do Angi and Zhang do when they want to check understanding？

A.They say: “Pardon？”

B.They repeat what they have heard.

C.They ignore the problem and do nothing.

D.They use body language, gestures or anything at hand to help understanding.

正确答案：They say: “Pardon？” ；They repeat what they have heard. ；They use body language, gestures or anything at hand to help understanding.