Not until I began to work ________ how much time I had wasted.
_____your poor record in school , we think you should study harder.
The young man, who had rushed into the fire to save the old man, _____ rewarding.
One should stick to ______one has begun.
It’s because he is in a hopeless situation, ______we will keep a very close eye on, ______ he looks depressed.
_____merely on what the average is , and you’ll remain average.