Summer is _______ good time for swimming, so you can find a good coach to help you in _______ summer of 2010.
Charles Babbage is generally considered ______ the first computer.
"Can’t you read?" Mary said ______ to the notice.
Look, they seem _____ about you.
My brother ______singing ______ dancing while I _____ dance _____sing.
Mr. Chen is a teacher and works very hard. _________ his wife.