Eggs, meat, vegetables and other foods can easily be poisoned by microorganisms such as ______.

One hundred percent _______ to your studies, though it can be lonely and no fun at all, will leave precious marks on your youth.

You are really very kind. I’ll never forget the _________ you have done to me.

—I’ve got an “A” in the examination. —That’s a good ______. You will surely win a second.

John says that his present job does not provide him with enough _____ for his organizing ability.