You ought to scrap the old bike and buy a new one.
你应该扔掉这辆旧自行车,买一辆新的。
It's not cricket to cheat at cards.
打牌时作弊是不应该的。
You should not take his statement on trust.
你不应该盲目相信他的这一番话。
(1)两者均用作情态动词,表示“应该”,常可替换,只是 ought to 语气稍重。例句:
The train ought to [should] have arrived at six. 火车本应该 6 点钟到的。
注:问句中用 ought to 时,对方除可用 ought (to) 来回答外,也可以用 should,例句:
A:Ought you to take him to a doctor at once? 你该马上送他去看病吗?
B:Yes, I should.是的,应该马上送去。
(2)出于法令规则、行为准则、道德责任等客观情况而“应该”做某事时,一般应用 ought to。用 should 则含有个人意见,强调主观看法)。
例句:We ought to go and see Mary tomorrow, but I don’t think we will.
明天我们按理应该去看看玛丽, 但是我认为我们不会去。
(3)在公告、须知或条例中,出于礼貌,常用 should,例句:
You should not run alongside the swimming-pool. 不准在游泳池边奔跑。