adj (1)确信的，肯定的，有把握的(having no doubt;certain)[无comp][作pred][A (of/about)，A+that，A+wh，A+wh-inf]：I'm not quite～. 我不十分肯定。I am～of his facts/his honesty. 我确信他的资料属实/他是诚实的。Do you feel quite～of that? 你对那非常有把握吗? Are you quite～about the telephone number? 你对这个电话号码有把握吗? I'm not～about/of his ability to cope with this. 我不敢肯定他有对付此事的能力。Are you～that you have locked the door? 你确信你已经锁门了吗? I was not～what I ought to do/where she lives. 我不知道我该做什么/她住在哪里。〖同〗confident，assured，convinced，positive，certain;〖反〗unsure，uncertain，doubtful，distrustful;

(2)肯(一)定会(有，得到……)(certain of having，receiving，winning，etc)[作pred][A(of)]：I feel～of success/her support/a profit. 我觉得我肯定会成功/得到她的支持/获利。You're～of a warm welcome. 你肯定会受到热烈欢迎的。

(3)肯(一)定会(做某事)(unlikely to fail to do or get)[无comp][作pred][A+to-inf]：He's～to win/refuse. 他肯定会赢/拒绝。It is～to rain. 一定会下雨。There's～to be some somewhere. 什么地方肯定会有一些的。They are～to have eaten everything up. 他们肯定把一切都吃光了。

(4)可靠的，信得过的(reliable or trustworthy)[通常作attrib]：a～friend 一个可靠的朋友;a safe，～method 一种安全可靠的方法;There is only one～way to succeed. 取得成功只有一种可靠的方法。have～knowledge of sb's promotion 有某人被提拔的可靠消息;make a～step out of the mud 从泥潭中跨出稳健的一步;〖同〗trustworthy，dependable，firm，faithful;〖反〗unworthy，faithless，untrue，undependable，unreliable;

be sure to do sth/be sure and do sth 一定要，千万：Be～to/and switch off the television. 一定要关电视机。Be～not to omit anyone from the list. 名单上千万不要漏掉任何人。

for sure 无疑地，有把握地：He would give us his decision for～by Wednesday. 周三以前他肯定会告诉我们他的决定。

make sure of/that 1)查明(弄清楚)：He looked behind him to make～he was not being followed. 他转身向后看以确保自己没有被跟踪。2)设法确保：Make～that the room is properly locked. 一定要把房间的门锁好。

sure of oneself 很自信：She seems very～of herself，but she isn't really. 她似乎很自信，但实际并不是那样。

sure thing 是的;当然(infml，尤AmE)：I've been luckier than a lot of people，～thing，but that doesn't mean I'm satisfied with things as they are. 当然我比许多人都幸运，但这并不是说我对现状很满意。

to be sure 诚然，肯定(fml)：He's a nice person，to be～，but not very clever. 诚然，他是个好人，但并不十分机灵。

→′sureness n 确切性;′sure-fire adj 必然的;

adv(1)确实，当然(certainly)(infml，尤AmE)：S～I'll help you. 我肯定会帮助你。“Would you like to come!”“S～!”“你来好吗?”“当然!”

sure enough 果然：I said it would happen，and～enough it did happen. 我说会发生的，果然被我说中了。

→′sure-footed adj 脚步稳健的;′surely adv 确实地;无疑地;必然地;

【辨异】sure与 certain、confident和positive的区别见CERTAIN。