It is the idea____smiles can get rid of cold ____has been proved by the researchers many times.
Never judge a man by his _____ alone--you might be fooled by what he looks like.
This book _______twelve units, ______two mainly revisions.
--Why does the lake smell terrible?--Because large quantities of water _______.
I hope, first of all, that we shall never lose _____ heart in face of _____ failure.
--Now, where is my purse?--______! We'll be late for the picnic.