Do you have _______ to tell us today, Lily?

Mr Hu, can you tell us how to learn math well?—Sure. But remember nothing can be learned _______ hard work. [ ]

A terrible earthquake happened in Wenchuan _______ May 12, 2008. [ ]

This is____ a difficult problem ____ all of us can’t work it out.

Polly’s mother was anxious about ______ she could get home safely in ______ foggy a day.