题目内容：
Directions: This part consists of a short passage. In this passage, there are altogether 10 mistakes, one in each numbered line. You may have to change a word, add a word or delete a word. Mark out the mistakes and put the corrections in the blanks provided. If you change a word, cross it out and write the correct word in the corresponding blank. If you add a word, put an insertion mark (^) in the right place and write the missing word in the blank. If you delete a word, cross it out and put a slash (^) in the blank.Example:
Television is rapidly becoming the literature of Our periods. 1. time/times/period
Many of the arguments having used for the study of literature 2. /
as a school subject are valid for/．Study of television. 3. the
Another thing to remember in connection with concrete is that you
are not allowed very much freedom for errors in either measurements and 1. ________
location. Once you have a solid mass of concrete set in place, it is going
to stay there. You have a very difficult job ahead of you if you try to
remedy a mistake. Make very sure, before you fill the form, which 2.________
everything is where and how you want it.
There are numerous niles regard the proper mixing, handling, and 3.________
finishing of concrete, and the essential one concerns the number of water 4.________
to use. The less water in the mix, the more the finished job will shrink. 5.________
The less water used, the harder and more enduring the job before it has 6.________
set.
The amateur concrete worker is plagued with two desires. One is to use enough water to have the concrete nice and soft and easy to push around. You have warned against that. The second is to take off the 7.________
wooden forms too early, to see how the job looks like. That is really 8.________
fatal. If the forms are stripped off too soon, while the concrete is still
"green", two things are likely to happen -- you are almost sure to break
off corners or edges, and you are unlikely to cause a major crack or 9.________
defect in the body of the work. An excellent rule is to wait until you are
sure the concrete is proper hardened, and then wait another day before 10.________
removing the forms.
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