EXERCISE 16 From the very beginning,water has furnished man with a source of food and a highway to travel.The first civilizations arose __1_ water was...
EXERCISE 17 According to government statistics,men of all social calsses in Britain visit pubs quite often,_1__ the kind of pub they go to may be diff...
EXERCISE 18 Each company has many "public" who would be able not only to recognize its name __1_ to correctly identify its industry and its ...
EXERCISE 19 During the 1980s,unemployment and underemployment in some countries was as high as 90 percent.Some countries did not _1__ enough food;basi...
EXERCISE 20 Predictions of many robots in industry have yet come true.For ten years or more,manufacturers of big robots have explained how their machi...
EXERCISE 21 Computer are now being pushed into school.We know that multimedia will make __1_ easy and fun.Children will happily learn from __2_ chara...
EXERCISE 22 In the past,the Park Service focused on making the big scenic parks more __1_ and comfortable for tourists.Road were paved to allow "...
EXERCISE 23 All the wisdom of the ages,all the stories that have delighted mankind for centuries, are easily and cheaply __1_ to all of us __2_ the c...
EXERCISE 24 Man has been storing up useful knowledge about himself and the universe at the rate which has been spiraling upward for 10000 years. The ...
EXERCISE 25 All immigrants must become permanent residents of the United States before they can __1_ citizenship.People who are residents carry with ...