题目内容
10．两个月以来，已经有400名大学生参加了"手机忍者"的测试．（take）400college studentshave already taken part in the test called Mobile Phone Ninja since two months ago．
分析 have already taken part in．
解答 答案：have already taken part in．这里参加的动作发生在过去，持续了一段时间，故用现在完成时have/has+过去分词，主语是students复数，故用have，参加结合所给的take用take part in参加，take的过去分词taken，已经用副词already放在have的后面，故答案是have already taken part in．
点评 现在完成时：
1．表示过去发生的动作对现在造成的影响或结果
2．表示过去的动作或状态持续到现在
3．构成 主语+have/has+动词的过去分词．
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19．
Tips for Writing Better Articles
Many of us don't spend a lot of time improving our writing skills．This can be a problem when we hand in our articles．Good writing skills will help us improve our grades and benefit us later in life．（56）B．
Make good word choices．When we're not sure which word is the right one for a sentence，look it up in a dictionary．Many of us choose words in a hurry and don't take the time to decide if they're proper．（57）E．
Check facts．If we want people to believe what we write，we must make sure our facts are true．We should use dependable facts．
Rewrite．A common problem is that we don't like to rewrite．In fact rewriting is the best way to find out and correct some mistakes，like grammar and spelling mistakes．（58）C，though it takes more time and more work．
Read aloud．Sometimes it's easier to find problem with spelling，word usage，and grammar when we read aloud．Reading aloud helps us not only find out our problems but also develop our writing．
（59）A．Preparing a list is necessary for writing a good article．Such a list includes：Is there a proper title？Have we explained every point？Are all the parts of the article included？This can help us to make sure that we have covered everything．
（60）D．But with a few simple steps，we can improve our writing skills and learn how to write better articles．
Tips for Writing Better ArticlesMany of us don't spend a lot of time improving our writing skills．This can be a problem when we hand in our articles．Good writing skills will help us improve our grades and benefit us later in life．（56）B．
Make good word choices．When we're not sure which word is the right one for a sentence，look it up in a dictionary．Many of us choose words in a hurry and don't take the time to decide if they're proper．（57）E．
Check facts．If we want people to believe what we write，we must make sure our facts are true．We should use dependable facts．
Rewrite．A common problem is that we don't like to rewrite．In fact rewriting is the best way to find out and correct some mistakes，like grammar and spelling mistakes．（58）C，though it takes more time and more work．
Read aloud．Sometimes it's easier to find problem with spelling，word usage，and grammar when we read aloud．Reading aloud helps us not only find out our problems but also develop our writing．
（59）A．Preparing a list is necessary for writing a good article．Such a list includes：Is there a proper title？Have we explained every point？Are all the parts of the article included？This can help us to make sure that we have covered everything．
（60）D．But with a few simple steps，we can improve our writing skills and learn how to write better articles．
| A．Prepare a list B．The following tips can be helpful C．Rewriting makes our writing better D．It is not easy to become a better writer E．Good word choices are necessary for good writing |