对于每个问题,他都回答“我不知道”。
To every question, he ___responded "I don't know."
我问她几点了,但她没有回应。
I asked her what the time was, but she didn't ___respond.
警察在几分钟内就能应对紧急情况。
The police ___respond to emergencies in just a few minutes.