It is the test system, the teachers,that is to blame for the heavy burden of middle school students nowadays。
Fred entered without knocking and, very out of breath, sank _______ a chair.
The open-air celebration has been put off _______ the bad weather.
Many of them turn a deaf ear to his advice, _____ they knew it to be valuable.
I’d like to study law at university __________ my cousin prefers geography.
Some students often listen to music _____ classes to refresh themselves.