five and a half hours 后面加什么动词 是 doing 还是 to do还是原形
问题描述：
five and a half hours 后面加什么动词 是 doing 还是 to do还是原形
完整的句子是 Did it take them five and a half hours 加comeback home by bus
答
A.如果句中含有动词spend 或者 spent(spend的过去式）,或者spends(第三人称单数）那么应该是doing
B.如果句子中含有take（或者take的各种时态,比如takes,或者took),那么应该用to do
C.如果句子中含有cost（或者cost的各种时态,比如costs),那么应该用to do
花费一段时间做某事有以下三种说法.
sb spend some time (on) doing sth----on 可以省略
=it cost sb some time to do
=it takes sb some time to do