There is a new problem involved in the popularity of private cars _______ road conditions need _______. 

It would be a good idea to use a plastic bottle, ___cut off, as a container to grow young plants in.

And if poverty is less of a problem and people are better educated，_______is a good chance that we will see less violence and fewer wars

—How are things going, Janet?—They have set out to deal with the present situation ________ they think deserves their immediate attention.

I’ll never forget the moment _____I first met Mary and _____ makes me already feel happy.