How long does it ___ to travel from TOKYO to Singapore by air?

问题描述:

How long does it ___ to travel from TOKYO to Singapore by air?
A. takeB. spendC. have D.cost
请教为何答案选A,而不是B? 并请详细说明 spend与 cost的区别.

因为句型是it takes sb.sometime to do sth
某人花了多长时间做某事
spend doing
cost 是物做主语 sth cost sb.