Animals should not be locked in cages; they should be in their normal _____.

　　A. environment B.position  C.residence  D. dwelling

He ate what he could, and gave the _____ of the food to the birds.

　　A. remain    B. uneaten    C. rest    D. part

The storm sweeping over this area now is sure to cause _____ of vegetables in the coming days.

　　A. rarity   B. scarcity  C. invalidity  D. variety

The open university was started in order to help those who _____ having a university education when they were young.

　　A. stopped    B. failed    C. missed    D. ceased

I shall take you back to Beijing _____ you are well enough to travel.

　　A. presently B. promptly C. immediately  D. shortly