The scientists 【小题1】 (决定探索) the deep ocean in order to find out what exists at the floor of the sea.Their first step 【小题2】 (实施这项计划) is 【小题3】 (派一台深水机器) designed specially for the research.【小题4】 (由科学家们远程控制的机器) at the surface of the sea is in a shape of an egg.They will watch the machine 【小题5】 (潜入大海深处).【小题6】 (进行这样的研究) is a long project that scientists have prepared for several months.

a. At that time people would 【小题1】 if food was difficult to find, especially during the cold winter months. Today’s festivals have many 【小题2】 some are religious, some seasonal, and some for special people or events.

b. His cola was【小题3】 and cold, and his ice cream was made of milk, cream and delicious fruit. “Nothing could be 【小题4】” he thought.

c. —And it was the ship that brought you to England.

—Yes. The fact is 【小题5】 I earned my passage by working as an unpaid hand, which 【小题6】 my appearance. I went to the American embassy to seek help, but…

d. Water had also appeared on other planets like Mars but, 【小题7】 the earth, it had disappeared later. It was not immediately obvious that water was to be 【小题8】 to the development of life.

e. Going eastward, you will pass mountains and thousands of lakes and forests, 【小题9】wide rivers and large cities. Some people have the idea 【小题10】 you can cross Canada in less than five days, but they forget the fact that Canada is 5500 kilometers from coast to coast.

Every living thing in nature struggles to survive. Most plants are 【小题1】 by animals and people, as well as by other plants, and may have to live in difficult conditions. Plants survive by 【小题2】 to life in different environments, and by competing 【小题3】 with other living things.

Over time, some plants develop features which help them to survive in particular conditions. Plants with helpful features are more 【小题4】 to survive and reproduce. Plants without these features often die out. The process is called natural 【小题5】.