a lot : 解析:　　a lot = lots(多用于口语中),可以有以下用法:

1. a lot可以用作副词,修饰形容词、副词或动词,在句中作状语,表示程度,其意义相当于much,very much或a great deal,有“很,极,经常”之意。例如:
He cares about you a lot. 他对你很关心。
My life has changed a lot in the last few years. 在过去的几年里,我的生活发生了许多(或很大的)变化。
She could speak several foreign languages, and she traveled a lot with her parents. 她会说好几门外语,而且跟她父母一起去过很多地方旅游。
a lot也可修饰比较级,作状语。例如:
I’m feeling a lot better today. 我今天身体好多了。
Going to school by boat must be a lot more fun than taking a bus. 坐船去上学一定会比坐公共汽车有趣得多。

2. a lot用作代词或名词,可指数或量,作主语和宾语等成分,等同于much。例如:
There was no TV at that time, so we didn’t know a lot about the world. 那时没有电视,所以我们对这个世界了解得不多。
My father knows a lot about computers. He’s a computer fan. 我父亲很懂电脑,他是个电脑迷。
I have heard a lot about you from Li. 我从姓李的那里听说了很多关于你的事情。
Later in his life, James Herriot wrote a lot about his experience as a country vet in Yorkshire, England. 后来在他的一生中,赫里奥特写了很多关于他在英国的约克郡当乡村兽医的经历的东西。
—How many do you want? 你要多少?
— A lot.(= Lots.)要很多。
What phone you have says a lot about you to some people these days.目前,你拥有什么样的手机会向别人说明关于你的许多方面。