at表示时间和地点
是个时间点,“工作”“时刻”与“圣诞”
at noon(night),in the day
表示某时某刻及在work,Christmas前用at.-My father are busily at work all day
at表示一个较小的地点,如在“入口”(entrance)“车站”(bus stop,railway station)和“影剧院”(cinema,theater)等名词前.home前一般用at,但若有物主代词和冠词等定语修饰时,须用in
-As she walked along,she noticed an old pine tree ahead at the entrance to a valley.
"for"
1.表示“当作、作为”.如:
I like some bread and milk for breakfast
2.表示理由或原因,意为“因为、由于”.
Thank you for helping me with my English
3.表示动作的对象或接受者,意为“给……”、“对…… (而言)”.
Let me pick it up for you
4.表示时间、距离,意为“计、达”.
We will stay there for two days
5.表示去向、目的,意为“向、往、取、买”等.
I paid twenty yuan for the dictionary
6.表示所属关系或用途,意为“为、适于……的”.如:
It’s time for school.
7.表示“支持、赞成”.如:
Are you for this plan or against it?
8.用于一些固定搭配中.如:
Who are you waiting for?