If you don’t know the answer you can say “ ”A. Thanks a lot.B. I’m sorry. I don’t knowC.

问题补充：

If you don’t know the answer, you can say,“ ”

A. Thanks a lot.

B. I’m sorry. I don’t know

C. Can you speak English?

D. Excuse me, Can you tell me the way?

答案：

A. Thanks a lot.

B. I’m sorry. I don’t know

C. Can you speak English?

D. Excuse me, Can you tell me the way?

解析：当我们不能帮助别人的时候，出于礼貌我们应该说抱歉，用sorry来表示，故选B。