删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1）每处错误及其修改均仅限一词；

2）只允许修改10处，多者（从第11处起）不计分。

    Friendship is important. Everyone need friendship. In all our lives we can't live without friendship just like we can't live without air and water. Friendship makes us get along well one another to go ahead under all kinds of difficulties in the front of us. But real friendship is not easy come by. True friendship must be sincere and be based on understand each other but not on the benefits from each other. A good friend can always be good teacher to us. He or she gives us some good advices on how to do things. So the more friends have, the better we can improve ourselves.

老一辈无产阶级革命家陈毅元帅，为了祖国的解放事业，戎马生涯几十年，遇到过无数艰难曲折，即使在最艰苦最残酷的年代里，他仍然对革命事业充满信心。陈毅元帅之所以能积极对待挫折，最重要的原因是（   ）

《史记·汉兴以来诸侯王年表》中记载：汉郡八九十，形错诸侯间，犬牙相临，秉其要塞地利，强本干，弱枝叶之势，尊卑明而万事各得其所矣。出现该现象的主要原因是（  ）