1）as+ adjective + as
例句：Listening to her was about as interesting as watching paint dry.
不过在口语里，我们有时会省略第一个as，像She looks white as a sheet.
2）like+ noun /verb phrase
The cruise ship was like a skyscraper lying on its side.
There are many idioms in which we use these two patterns:
You are as white as a sheet I think you 'd better see a doctor.
I feel full of energy today -I slept like a dog last night.
You look as a man who's seen a ghost!这个是不恰当的表达，正确应该是：You look like a man who's seen a ghost！
或者如：When Mike puts on his dark suit he looks like a waiter (= He resembles a waiter.)
比如： Rachel's working like a waiter during the summer vacation的正确表达应该是Rachel's working as a waiter during the summer vacation. (This is her job.)