用所给词的适当形式填空:You shoud thing over the question carefully before ( )(answer)it

问题描述:

用所给词的适当形式填空:You shoud thing over the question carefully before ( )(answer)it
急,请尽快帮助,要解析

answering
此处answering是主语,动词做主语要变成动名词,所以是answering