How can you expect him to make any improvement________ you never give him a chance to have a try?[ ]

In the reading room, we found her _____ at a desk with her attention _____ on a book.

23．You have worked hard all week so you ____ a good rest．

In many countries in the world ,breakfast is a snack____a meal,but the traditional English breakfast is a full meal[ ]

________ any other species, human populations are shaped by the usual forces of natural selection, like famine, disease or climate[ ]