phr. let alone 1. 不打扰，不惊动
He is gentle as a lamb when he is let alone. 他不受惊扰时，温顺得像一头小羊。
Let the poor little cat alone. 别去惹那只可怜的小猫。
2. 更别提
I've not even read the first chapter, let alone finished the book. 我连第一章还没看，别说读完全书了。
Englishmen themselves, letalone foreigners, are often uncertain what is slang and what isn't. 英国人自己也常常不能确定什么是俚语，什么不是俚语，更不要说外国人了。
let be 不打扰，使维持原状
Why don't you let the child be when he's not feeling well! 孩子身体不舒服，你为什么不让他独自安静一会儿!
let down 1. 放下；降下
She let down the blinds. 她放下窗帘。
Harry let the chain saw down on a rope and then came down himself. 哈里用绳子把链锯吊下，然后自己再下来。
2. 放松；松懈
This is no time for the world to let down its guard agaist terrorism. 现在不是世界人民可以对恐怖主义放松警惕的时候。
The horse let down near the end of the race and lost. 那匹赛马在将到终点时松了劲，于是败北。
3. 使失望，使沮丧，对…失约；(在紧要关头)抛弃，不支持
They felt the school system had let them down. 他们感到学校制度令他们失望。
She felt let down when he didn't phone her. 他没给她来电话，她感到沮丧。
He's been let down so much in the past that he trusts no one. 他过去受挫折太多，因此对谁也不信任了。
Dont' let me down， I need your support. 别撇下我不管，我需要你的支持。
4. (飞机或飞机驾驶员在着陆前)下降
The aircraft is letting down to land. 飞机正向地面下降。
5. 使屈辱，使丢脸
let sb. down gently (或 easy, easily) 给某人留点儿面子
If you don't tell the truth, you will let me down badly. 要是你不说实话，那就太让我下不了台了。
The irate colonel blared at the troops for letting down the regiment. 怒气冲冲的上校向士兵们吼叫，因为他们给全团丢了脸。
6. 放长(衣服)；放出(褶边)
These clothes are too short. They need to be let down. 这些衣服太短了，需要放长。
7. 〈英〉(放气)使瘪凹
Someone let down my bicycle tyres. 有人把我的自行车轮胎放了气。
let drive (at) 见 drive
let fall (或 drop) 1. 掉落，掉下
She was so startled that she let fall everything she was carrying. 她吓了一大跳，手里拿的东西全掉了。
2. 脱口说出
She let it fall that he was seriously ill. 她无意中说出他病得很重。
3. 【数】向一直线作(垂线) (on, to)
let fly (at) 见 fly²
let go 1. 放；释放
The dog ran away when John let it go. 约翰把狗一放开，它就跑掉了。
2. 松手；使射出，发射
Let go (of) the rope. 松开绳子。
He let go without warning me and I fell backwards. 他没说一声就松了手，害得我仰天摔了一跤。
The hunter let go an arrow at the hare. 猎人对野兔射出一箭。
The soldiers let go a number of shots. 士兵们射出多发子弹。
3. 放弃(of)
They promise to let go of most of the territories they have occupied. 他们答应放弃他们所占领的大部分领土。
4. 断裂，破裂
The old water pipe suddenly let go. 旧水管突然破裂了。
5. 对…不予考虑，对…不予讨论；对…不予理会
You've made a small mistake, but we'll let that go. 你犯了个小小的错误，但我们不准备追究了。
The children teased Frank, but he smiled and let it go. 孩子们嘲弄弗兰克，但他只是付之一笑，不加理会。
6. 不注意保养，忽略
let one's teeth go 不注意保护牙齿
The garden has been let go a bit. 花园有些荒芜了。
7. 不拘束，洒脱
He can let go in private. 他在无旁人的情况下会很轻松自然。
8. 〈婉〉解雇
Some of the faculty were let go for lack of students. 由于生源不足就让一些教职员离职了。
let in 1. 允许进入；漏水
let in a flood of light 放进一大片强光
He let them in by a side door. 他让他们从边门进入。
This would let in all sorts of evils. 这会使各种罪恶乘虚而入。
This pair of boots is letting in badly. 这双靴子漏得厉害。
2. 让…知情；允许…参加
3. 使遭受损失；使陷入；惹起
I was badly let in over that business. 我在那桩生意上大受损失。
4. 镶嵌
5. 把(衣服)改窄
Your dress needs letting in at the waist. 你这条连衣裙腰部需要改窄些。
let in for 〈口〉使陷入，使卷入；惹起(麻烦等)
He let himself in for a lot of extra work. 他给自己招来许多额外工作。
His tactlessness lets me in for a lot of embarrassment. 他太不策略，弄得我非常尴尬。
let in on 1. 让(某人)得知(秘密等)
I think we'll have to let your mother in on our plans. 我认为我们必须让你母亲知道我们的打算。
2. 让(某人)参与
He was let in on the arrangements without our consent. 我们还没同意，就让他参与了种种安排。
let into 1. 允许进入
I'll let you into the house. 我会让你进屋的。
2. 把…插入，把…嵌入
let a pipe into the wall 把管子插进墙
a shelf let into the study wall 嵌进书房墙壁的书架
3. 使知道(秘密等)
Shall we let Mary into our secret? 我们要把秘密告诉玛丽吗?
4. 攻击；拳打，责骂
He was so infuriated that without a word he let into the rascal. 他勃然大怒，二话不说就揍了那流氓一顿。
let it drop (或 rest) 不再说(或做)某事
let it go (或 pass) (对某一行动或话语)不做出反应
let it go at that 〈口〉不去多操心；不再多说
He said he hadn't understood the rules, and we let it go at that. 他说他不懂这些规则，我们也就算了。
let loose 见 loose
let me see 见 see¹
let me tell you 见 tell¹
1. 排放(液体等)
The locomotive suddenly let off steam. 火车头突然放出蒸气。
2. 放过；宽恕；对…从轻处理
All right, I'll let you off this time, but never again! 好吧，这次我饶了你，但决不许再犯了。
He was let off with a year on probation. 他受到缓刑一年的宽大处理。
3. 准许…暂停工作(或不必工作)
Let the workmen off early. 让工人们早点下班。
I'll let you off doing the washing up. 我免了你洗碗碟的活儿。
4. 允许…下(车或船)
Would you let me off (the bus) at the next stop,please? 请你下一站让我下车好吗?
The guard won't let anyone off the train between stations. 列车员不会让任何人在站与站之间下车。
5. 放(枪、炮、烟火等)；说(笑话等)
He let the gun off in error. 他让枪走火了。
Small boys let a few fireworks off. 小男孩们放了一些烟火。
Suddenly he let off a joke and the tense atmosphere at once relaxed. 他突然说了句笑话，于是紧张气氛立即缓和下来。
6. 〈主英〉分开出租(房屋)
The fine old house is being let off as flats. 这所漂亮的老房子分作几套出租。
let on 〈口〉
1. 泄露(秘密)；流露真情
He never let on that he was married. 他从不透露自己已结婚。
Never let on to anybody. 千万别对任何人说。
She knew where the children were hiding but she didn't let on. 她知道孩子们藏在哪儿，但是不露声色。
I think you understand more than you let on. 我想你了解的要比你透露的多。
2. 假装
let on to being a stranger 假装是陌生人
She likes to leton that she is rich. 她喜欢装模作样，让人以为她很有钱。
let oneself go 1. 放松；不再操心
2. 放纵，随心所欲
At the party she just let herself go and had a great time. 她在晚会上纵情欢乐，过得十分愉快。
3. 变得不修边幅
He looks awful. He's let himself go since Mary died. 他看上去衣冠不整。自从玛丽死后他变得不修边幅了。
let oneself in (用钥匙)开门进入
let out 1. 放走，释放
let out the dog 放狗出去
Who let the air out of my tyres? 谁把我轮胎的气放了?
let sb. out of prison on bail 把某人保释出狱
2. 发出
The dog let out a yelp. 狗发出吠声。
3. (拆出褶缝等)放大(衣服)
I've got so fat that I'll have to let the waistband out several inches. 我发胖了，得把腰带放出几英寸。
4. 出租
let out rooms 出租房间
5. 〈美口〉解散；放学；散场
I'll meet you after school lets out. 我放学后跟你碰头。
6. 〈美口〉〈婉〉解雇
be afraid of being let out 害怕被解雇
7. 痛打；痛骂；踢(at)
That horse has a habit of letting out at people. 那匹马好踢人。
8. 泄漏，使知道
Keep this to yourselves — don't let it out to the press. 这事你们要严守秘密，不要向报界透露。
It is time to let the secret out. 现在是公开这个秘密的时候了。
9. (为求美观合身)把(毛皮)裁成斜条后缝合
let pass 放过；对…不予理会
The teacher said that he could not let the child's disobediences pass. 老师说他不能轻饶那孩子不服管教的行为。
What the newspaper said isn't at all accurate, but let that pass. 报纸报道根本不准确，不过让它去算了。
let sb. have it 〈口〉
1. 打击某人；向某人射击；用刀刺某人
The gunman threatened to let the teller have it if he didn't obey. 武装匪徒威胁出纳员，要是不顺从就开枪打死他。
2. 谴责某人；攻击某人；批评某人
Mary kept talking in class until the teacher became angry and let her have it. 玛丽上课时老是讲话，直到老师生气把她批评了一顿。
let's face it 见 face
let slide 〈口〉对…听其自然
You should not let your studies slide. 你不应该学习上放任自流。
let slip 〈口〉
1. 放开，放手
When the game was started, the hunters let the dogs slip. 当猎物惊起时，猎人们纵狗追赶。
2. 无意中吐露
let slip the truth 无意中吐露实情
3. 放过，错过
He was invited to America several years ago but he let the chance slip. 几年前他被邀请去美国，但他放过了那次机会。
let's say [用作插入语]比如说
let's you and me (或 you and I, you and us, us) 〈美口〉让我们
Let's you and me get to work. 咱们开始工作吧。
Let's you and I go west. 我们朝西走吧。
Let's you and us go for a ride. 我们去骑马吧。
Let's us go too. 让我们也去吧。
let through 允许…通过
A number of mistakes in the proofs were let through. 校样中有好些错误被漏过了。
let up 〈口〉
1. 停止；暂停
The rain will soon let up. 雨很快就会停的。
2. 放松；减弱，减小，减轻，缓和
His mind never let up for an instant. 他思想上一刻也没有放松过。
The wind is letting up a little. 风势小一些了。
let up on 〈口〉较宽容地对待
Let up on her. She is sick. 别对她太严厉了，她在生病。
let us say= let's say
let us see见see¹
let well(enough) alone 见 well¹