是　right

　"Is this book a dictionary?" "Yes, it is."　“这是一本词典吗?”“是的。”
　"Is there anything you need?" "Yes, there is."　“你需要点什么吗?”“是的，需要。”
　"Don't you want to come with us?" "Yes, of course I do."　“你难道不愿意和我们呆在一起吗?”“当然愿意。”
　"English is a difficult language." "Yes, but not as difficult as Chinese."　“英语很难。”“是啊，但没有汉语那么难。”
　"Isn't she sweet?" "Yes, she is."　“她很可爱吧?”“对，她很可爱。”
　Yes, what you say is right.　不错，你说的是对的。
　"Can I borrow this record?" "Yes, of course."　“我可以借这张唱片吗?”“当然可以。”
　"Coffee?" "Yes, please."　“要咖啡吗?”“要，谢谢。”
　"Williams." "Yes, sir."　“威廉姆。”“到。”
　"Go and close the door." "Yes, sir."　“去把门关上。”“是的，先生。”
　"Waiter!" "Yes?What can I do for you?"　“服务员！”“您需要什么?”
　"Yes, please go with us!"　“跟我们一起去吧！”
　"Yes?" "I'd like two tickets, please."　“要什么?”“请给我两张票。”
　His composition is good, yes, very good.　他的作文很好，是的，很好。
　Tom is a good student, yes, the best in the class.　汤姆是个好学生，是的，是班里最好的。
　He smiles on you, yes?　他在对你笑，对吗?
　"You haven't got a pen, have you?" "Yes, I have."　“你没有钢笔，是吗?”“不，我有。”
　"You didn't mean to go there alone?" "Yes, I did mean it."　“你不想一个人去那儿?”“不，我想。”

　你今晚不出去吗?——不，不出去。
　［误］ Aren't you going out this evening?— Yes, not this evening.
　［正］ Aren't you going out this evening?— No, not this evening.
　“你星期天不上班，是吧?”“是，不上班。”
　［误］ "You aren't working on Sundays, are you?" "Yes, I'm not."
　［正］ "You aren't working on Sundays, are you?" "No, I'm not."
　［析］ 不管前半部分陈述句是肯定式还是否定式，附加疑问句部分的简短答语都要依“事实”而定。简短答语中的谓语动词是肯定式，则可用Yes作答，如谓语动词是否定式，则须用No作答。

　［反义词］ no
　［词源］　古英语gese（是的）