1.V-T If you forget something or forget how to do something, you cannot think of it or think how to do it, although you knew it or knew how to do it in the past. 忘了 (某事物、如何做某事)
例：
She forgot where she left the car and it took us two days to find it.
她忘了把車停在了哪裏,我們花了兩天時間才找到它.
2.V-T/V-I If you forget something or forget to do it, you fail to think about it or fail to remember to do it, for example, because you are thinking about other things. 忘記 (某事物、做某事)
例：
She never forgets her daddy's birthday.
她從不忘記她爸爸的生日.
She forgot to lock her door one day and two men got in.
她有壹天忘了鎖門,結果兩名男子進去了.
When I close my eyes, I forget about everything.
我閉上眼睛就忘記壹切.
3.V-T If you forget something that you had intended to bring with you, you do not bring it because you did not think about it at the right time. 忘記帶 (某物)
例：
Once when we were going to Paris, I forgot my passport.
有壹次我們去巴黎時,我忘了帶護照.
4.V-T/V-I If you forget something or someone, you deliberately put them out of your mind and do not think about them any more. 忘掉 (某事物、某人)
例：
I hope you will forget the bad experience you had today.
我希望妳會忘掉妳今天的這次不愉快經歷.
I found it very easy to forget about Sumner.
我發現要忘掉薩姆納很容易.
5.CONVENTION You say "Forget it" in reply to someone as a way of telling them not to worry or bother about something, or as an emphatic way of saying no to a suggestion. 沒關系; 休想
例：
"Sorry, Liz. I think I was a bit rude to you."—"Forget it, but don't do it again!"
“對不起,莉茲.我想我剛才對妳有點粗魯.” —“沒關系,不過以後別再這樣做了!”
6.PHRASE You say not forgetting a particular thing or person when you want to include them in something that you have already talked about. 別忘了 (某物或人)
例：
Leave a message, not forgetting your name and address.
留張條,別忘了留下妳的姓名和地址.
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