1.a little adv. 略微，稍微和a bit adv. [尤英]略微，一点
几乎可以通用，但 a bit 较口语化，且从表示的程度上讲，a bit 稍弱于 a little。故有时为了加强语气，在 a bit 中间加上 little。
请看经典例句：
It is a little cold today.
今天有点儿冷。
He has grown a little taller.
他稍微长高了一点。
Modern furniture is a little too severe for my taste.
现代家具有点过于简朴，我不大喜欢。
I could just eat a little something.
我只能吃一点点东西。
Try to put a little more expression into it!
尽量注入更多的感情！
He's starting to get a little thin on top.
他开始有点谢顶了。
I find his attitude a little hard to take.
我觉得他的态度有点儿令人难以接受。
Let's go somewhere a little less public.
咱们找一个僻静些的地方吧。
You could try being a little more encouraging!
你可以试着多给人一些鼓励嘛！
I should wait a little longer, if I were you.
假如我是你的话，我会再等一会儿。
I'll be a little later home tomorrow.
明天我要晚点儿回家。
She's a little vague about her plans for next year.
她对她明年的计划不怎么明确。
The discussion got a little heavy.
讨论变得有点严肃。
I’ll be a bit/ a little later home tomorrow.
明天我要晚点儿回家。
That's a bit/little odd.
那有点儿奇怪。
She felt a bit/little tired.
她觉得有点儿累。
Please wait a little bit.
请稍等片刻。
Your report is a bit long.
你的报告长了一点。
You need to work on your pronunciation a bit more.
你需要再加把劲改进发音。
It costs a bit more than I wanted to spend.
它比我预计的消费高了一点。
I feel a bit down today.
我今天有点闷闷不乐。
Can you turn the volume up a little bit?
你能把音量开大点儿吗？
I got paid a little bit of money.
我只领到了一点点钱。
These shoes are a little bit too tight.
这鞋有点儿紧。
I just think you're getting a little bit above yourself.
我只是觉得你变得有点自视过高。
He was a little bit afraid of his father's reaction.
他有点害怕父亲的反应。
Maybe we'll hear a little bit less noise.
也许我们听到的噪音会稍微少一点儿。
I really didn't like New York, but I wanted to stick it out a little bit longer.
我真的不喜欢纽约，但我想再坚持一段时间。
You know these last few months when we've been expecting it to warm up a little bit?
你知道最近这几个月我们一直盼望着天能暖和一点吧？
He was a little bit cocky when he was about 11 because he was winning everything.
11岁左右的时候，他就有点自以为是，因为他那时从未失败过。
It must be said that the defence minister is a little bit more dovish than other people in the ruling elite.
需要指出的是国防大臣比上层统治集团中其他成员都要温和。
2.a little 和a bit of可以作形容词修饰不可数名词，几乎可以互换，区别在于a bit 较口语化，且从表示的程度上讲，a bit 稍弱于 a little。故有时为了加强语气，在 a bit 中间加上 little。
注意：.a bit 不能直接修饰名词，应该用 a bit of，为非正式用语。
He speaks a little German.
他会说一点点德语。
I have a little money in the bank to fall back on.
我在银行还有一点钱，需要时可以动用。
I go to the library for a little peace and quiet.
我到图书馆去清静一下。
She needs a little water.
她需要一点水。
Let's listen to a bit of music.
我们来听点音乐吧。
They're worth quite a bit of money.
它们值不少钱。
A bit of exercise will help lift his spirits.
进行一点儿体育锻炼能帮助他改善情绪。
She's done quite a bit of work this past year.
过去的一年里她做了不少工作。
特别注意： a bit of+不可数名词，表示一点……，也可以： a bit of+a(an)+名词，但是表示有点像这个名词所表达的含义。请注意琢磨这个用法。
I've come looking for a bit of advice.
我特来讨教。
With a bit of luck, we'll finish on time.
如果我们运气好，就能够准时完成。
With a bit of luck, we'll be there by 12.
如果顺利点，我们将于12点钟赶到那里。
She'd do anything for a bit of pin money.
为了挣点外快，她什么都肯做。
Well, actually it requires quite a bit of work and research.
嗯，实际上这需要花不少的工夫，做点研究。
It's just a bit of harmless fun.
开个小玩笑罢了，并无恶意的。
He's a bit of a mystery.
他这个人有点儿神秘。
He seems to be a bit of a philosopher.
他像个思想家似的。
He's a bit of a rogue, but very charming.
他好捣蛋，但却很讨人喜欢。
Tony was a bit of a lad ─ always had an eye for the women.
托尼这小子真是个花花公子——总是很会欣赏女人。
The whole place was a bit of a dog's dinner, really.
整个地方乌烟瘴气的，真的。
I think I've got a bit of a stomach bug.
我想我的胃可能出了点儿毛病。
To be frank, he could also be a bit of a bore.
老实说，他有时也会让人厌烦。
I made a bit of a boob throwing that file away.
我犯了个愚蠢的错误，把那份文件扔掉了。
She worked herself up into a bit of a state.
她把自己弄得有点儿紧张。
Students have always been portrayed as a bit of a joke.
学生们总是被描述为有点儿可笑的人。
Seven people in the car was a bit of a squeeze.
那辆车坐了七个人是有点挤。
The rail strike is a bit of a pain.
这次铁路罢工有点头痛。
3.a bit of后可以接动名词：
I've got a bit of shopping to do.
我要买点东西。
I'm sure he'll come with a bit of persuading.
我相信，劝一劝他就会来的。
4.否定结构含义不同
a little：not a little意思为“非常”，相当于“very”。例如：
He is not a little tired.=He is very tired.他很累。(他不是一点儿的累)
She was not a little worried about the expense.
她对那笔开支相当苦恼。
After a whole day's work, I was not a little tired.
过去一整天，我感到很累。
He was not a little surprised when he heard the news.
听到这个消息时很惊奇。
a bit和a little与否定词not连用时，两者的含义是不同的。
a bit：not a bit意思为“根本不/一点也不”，相当于“not at all”。例如：
I'm really not a bit surprised.
我真的一点儿也不觉得惊讶。
Did he give up? Not a bit of it!
他放弃了吗？根本没有！
He is not a bit tired.=He is not tired at all.他一点儿也不累。
Did he give up? Not a bit of it!
他放弃了吗？根本没有！