The new hospital will be located in _________ used to be a wasteland and a huge shopping mall will also be constructed ________ there used to be a school many years ago.

The government has taken some measures to solve the shortage of electricity , but it may be some time _________the situation improves.

Tom raised his hands      to say something, but he remained silent in the end.

Some people have the idea_____ you can cross Canada in less than five days.

______ is even more important is that the earth cooled down, water began to appear on its surface.

It is so wet there _____ the trees are extremely tall, some measuring over 90 meters.

They are putting too much carbon dioxide into the atmosphere, ______ prevents heat from escaping from the earth into space.              

It will be at least three weeks________ he recovers from his illness and returns to work.

He made a mistake，but he corrected the situation       it went worse．

In the US, students can do almost anything they want in class, ____ they don’t make too much noise or disturb others who want to learn from the teacher.