1 . On the tables sat a box________ (装饰)with little pearl triangles. （根据汉语提示单词拼写）

2 . Diets are most effective if _______（将……和……结合）exercise. (根据汉语提示完成句子)

3 . With his attention ________ on his book, he noticed nothing.

A．concentrated

B．concentrates

C．concentrating

D．to concentrate

4 . So much carbon dioxide is ________ (排放) that it results in global warming. (根据汉语提示单词拼写)

5 . He was doing his homework one Sunday morning when he smelt something ________.

A．burnt

B．to be burnt

C．having been burnt

D．to burn

6 . Be careful when you deal with this chemical, as it will explode when        to sunlight.

A．being exposed

B．to expose

C．exposing

D．exposed

7 . At the tenth international Ballet Competitions, Lisa won the first gold medal ever ______(授奖) to an American male dancer. (根据汉语提示单词拼写)

8 . According to a report ______（发布） by an environmental research group, about one billion live in unplanned settlements. （根据汉语提示单词拼写）

9 . Almost everywhere you go in the UK, you will find yourself ________(包围) by evidence of four different groups of people who took over at different times throughout history. (根据汉语提示单词拼写)

10 . ________ in 1636, Harvard is one of the most famous universities in the world.

A．To found

B． Founding

C．Founded

D．Having been founded