AIDS is said _______the biggest health challenge to both men and women in that area in the past three years.

People read newspapers and magazines inorder to keep themselves _________ ofwhat is going on in the world outside

There are two trees . One bird is singing in _____tree and two boys are sitting under ____.

–Guess what! We’ll have a chance to visit our sister school in Denmark this summer!–How nice! You ______ a different culture then.

It is widely believed that children should drink enough milk, which can _____ their healthy growth.