Whenever something goes wrong, everyone blames it ___ me.
If you really have to leave during the meeting, you’d better leave _________ the back door.
Fred entered without knocking and, very out of breath, sank _________ a chair.
The open-air celebration has been put off __________ the bad weather.
__________ fire, all exits must be kept clear.
Some students often listen to music __________ classes to refresh themselves.