最常见最简洁的表达：
Sorry to keep you waiting.
如果你是个迟到大王，这句话你一定要学：Sorry to keep you waiting.（对不起，让你久候）。这句话不论在日活生活或在电话在线要别人久等都可用得着，此外也可说：Sorry I couldn't be on time.（对不起，我不
能准时到达）。
对话
A: Hey Marcus, where were you? We've been expecting you all night.
B: Sorry to keep you waiting. I had an important meeting and it ran over.
A: How's business been recently?
B: Well, not too bad.
甲：唏，马吉斯，你去了哪儿？我们整晚等着你。
乙：对不起，要你们久候。我有个重要会议，开到过了时。
甲：生意最近如何？
乙：蛮不错吧。
有些人迟到，会说：Sorry to keep you waiting，有些则会说：Sorry to have kept
you waiting.（对不起，要你们久候了），究竟哪个说法才正确？
说为现在的事抱歉，sorry之后用‘to + 原形动词(infinitive)’或‘that + 子句(clause)’都可以，例如：(1) I'm sorry to interrupt, but there's a long-distance call for you.
（对不起，打扰了，有长途电话找你）。(2) I'm sorry (that) I'm late（对不起，我迟到了）。
说为过去的事抱歉，sorry之后用‘for/about + ing形式动词’或‘to have + 完成时动词(perfect tense)’或‘that + 子句’，例如：(1) I'm sorry for calling you a
liar.（我曾说你不诚实，真对不起）。(2) I'm sorry to have called you a liar.
(3) I'm sorry (that) I called you a liar.
迟到者说‘要你们久候了’，那等候在他到达时即成过去，所以有I'm sorry to have
kept you waiting这说法。不过，由于等候才刚刚结束，当作现在的事并无不可，所以也有I'm sorry to keep you waiting. 的说法，两句意思没有什么分别。
迟到最好可以解释原因。一个常见原因是交通阻塞：I got stuck in traffic.（我在车辆之中动弹不得）或Traffic was slow.（路上车辆缓慢）。另一原因是：I overslept.（我睡过了
头）或My alarm didn't go off.（闹钟没有响）。当然，真正的原因可能是时间估计错误：I misjudged the time.
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