“某人花不少时间去做某事”的英文翻译?

it takes sb.a lot of time to do sth.
sb.spend a lot of time (on) doing sth.
如果是想用it takes的话,要用介词to
如果是想用spend的话,就要用介词on
(怎么会有spend...to..或者spend...in..>.