Tom, clean up the broken glass _________ someone walks on it.
You can't work out this problem ___in this way.
I had no idea ____ is better, so I took ____ of them.
The headmaster hurried to the concert hall only ___ the speaker ____.
The thing that_____ is not whether you fail or not, but whether you try or not.
_____ is no need to argue again the problem.We settled it at the last meeting.