1£®The plant Professor Li is studying exists (exist) only in Australia.

2£®The course is designed to help students to understand the structure of those two systems (system)£®

3£®Scientists developed several theories (theory) on what else might determine which hand you write with.

4£®Because of the violent (violence) wind, many people couldn't go to work.

5£®The four­year­old Russian girl has drawn global (globe) attention for her great gift for languages.

6£®Unlike (like) the tradition in the West, the family name in China is put first, which is followed by the given name.

7£®The air is harmful (harm) to health, so you mustn't enter the room.

8£®Over the past ten years, Mr. Green has_multiplied (multiply) his money many times.

9£®We were puzzled (puzzle) about the sudden disappearance of our guide at that moment.

10£®The government is spending billions (billion) of dollars on new rail projects.