I sometimes waver ________continuing to study and starting up.

We benefit greatly ____________the medicines and other products that biodiversity provides.

We are here to provide you_____ the best service possible.

House cats are distantly related ______ lions and tigers. 

Is this type of soil suitable ___ growing tomatoes?

My husband and I take turns cleaning ________ the kitchen depending ________ who gets home from work earlier.

One meter is approximately equal ________a yard.

Many places _____ our city are heavily polluted.

Jane doesn't spend much money _____ clothes.

Tom's grandmother died _______1977 _______ the age of 79.

Alice opened the door and found that it ________ to a small passage.

Thomas has often boasted ________ his son's golfing ability.

He succeeded________ getting a scholarship.

The course begins _______7 January and ends _________10 March.

Water consists_____ oxygen and hydrogen.

Tom isn't here _________ the moment. He'll be back _________five minutes.