往往只看到“牛人”闪耀的成绩，却忽视其成绩背后的勤奋。要知道，那些闪耀的成绩都是汗水换来的，为帮助考生提升成绩，小编整理了成人英语三级考试完形填空练习及答案四，赶快练习吧！
Can you imagine living and working in a one-man submarine (潜水艇)? Scientists believe that 1C one-man submarines will be as 2B as automobiles are today.
你能想象自己在一个单人潜水艇里工作生活吗?科学家们相信，终有一天单人潜水艇的数量将会和今天汽车的数量一样多。
First, 3B , the human problems involved 4B the ocean living will need to be studied in 5C , and scientists have already begun to work in 6C fields as marine biology, ocean currents, and ocean-bottom geology.
因此，首先，人类的问题涉及到详尽地研究海洋生命，科学家们已经开始研究海洋生物学，洋流以及海底地质学。
7B studying ocean plants and animals, science may find a(n) 8C for some of our most serious diseases. And we may learn to use 9D plants to increase our world food supply 10D .
通过研究海洋动植物，科学家们可能找到医治一些————严重疾病的方法。同时，我们也可以学习如何利用海洋植物以增加全球食物供应量。
11C new tools and machines, mining engineers may make 12D possible to get valuable 13B from the ocean. 14C , ocean minerals renew themselves, 15A land minerals, which are gone forever 16C taken out of the earth.
使用新型的工具和机器，采矿工程师将可能从海洋获得珍贵的植物。很有希望的是，海洋矿物质能够再生，而不像陆地上的矿物资源，一旦从土壤中挖掘出来将不可再生。
Above all, the sea has 17A of space, not 18C for floating communities and parks, but also for 19B supplies and for underwater travels.
毕竟，海洋有充足的空间，不仅可以用于人类居住的海上漂浮社区和公园，还能用于存储食物和水下旅行。
Indeed, ocean living will help man in more than physic ways. In the freedom and beauty of the deep sea, man may 20B new sources of joy.
确实海洋生命对于人类的帮助不仅仅是具体的。人类能从深海处的自由和美丽中获得新的乐趣。
1. A. sometimes B. somehow C. someday D. somewhat
2. A. much B. many C. well D. fine
3. A. however B. therefore C. though D. of all
4. A. on B. in C. at D. for
5. A. fact B. general C. detail D. short
6. A. the B. same C. such D. other
7. A. With B. By C. On D. For
8. A. key B. way C. cure D. answer
9. A. better B. cheaper C. water D. sea

10. A. yet B. also C. too D. as well
11. A. Through B. To C. With D. In
12. A. something B. them C. things D. it
13. A. foods B. metals C. plants D. animals
14. A. Possibly B. Hopefully C. Fortunately D. Naturally
15. A. unlike B. as C. besides D. dislike
16. A. while B. before C. once D. when
17. A. plenty B. vast C. enough D. many
18. A. really B. yet C. only D. simply
19. A. maintaining B. storing C. protecting D. preventing
20. A. take B. find C. feel D. make