spend,cost,take和pay都表示“花費”。
spend的主語必須是人。
(1)spend time/money on sth. 在...上花費時間/金錢 例：I spend two hours on this maths problem.
(2)spend time /money (in) doing sth. 花費時間/金錢做某事 例： They spend two years(in) building this bridge.
(3)spend money for sth .花錢買.... 例：His money was spent for books.
cost的主語是物或某種活動，還可以表示“值”
(1)sth.costs(sb.)+金錢 某物（做某事）花了（某人）多少時間。 例：A new computer costs a lot of money.
(2)(doing) sth costs(sb.) +時間。 某物（做某事）花了（某人）多少時間。 例：Remembering these new words cost him a lot of time.
注：cost的過去式和過去分詞都是cost,並且不能用於被動句。
take後常跟雙賓語，常見用法：
(1)It takes sb.+sometimes+to do sth. 做某事花了某人多少時間 例：It took them three years to build this road.
(2)doing sth takes sb.+時間， 做某事花了某人多少時間 例：Repairing this car took him the whole afternoon.
pay的基本用法
(1)pay(sb.)money for sth. 付錢（給某人）買...。 例：I have to pay them 20 dollars for this room each month.
(2)pay for sth. 付......的錢。 例：I have to pay for the book lost.
(3)pay for sb. 替某人付錢 例：Don't worry! I'll pay for you.
(4)pay sb. 付錢給某人。 例：They pay us every month.
(5)pay money back 還錢 例：May I borrow 12 yuan from you? I'll pay it back next month.
(6)pay off one's money 還清錢