一道高中英语语法填空

答：这是根据英语伍前美文:The Story Of The Farmer And His Donkey 改编的语法填空题。
One day a farmer's donkey fell down into a well. The animal cried piteously for hours as the framer tried to figure out what to do. Finally he decided the animal was old, and the well needed to be covered up anyway and【 it just wasn't worth to retrieve the donkey】. So, he decided to bury it!
He invited all his neighbours to come over and help him. They all grabbed a shovel and began to shovel dirt into the well. At first, the donkey realized what was happening and cried horribly, then slowly he quieted down till nothing more was heard.
A few shovel loads later, the farmer finally looked down the well, and was astonished at what he saw. With every shovel of dirt that hit his back, the donkey was doing something amazing! He would shake it off and take a step up!
As the farmer's neighbours continued to shovel dirt on top of the animal, he would shake it off and take a step up. Pretty soon, everyone was amazed as the donkey stepped up over the edge of the well and trotted off!
Life is going to shovel dirt on you, all kinds of dirt. The trick to getting out of the well is to shake it off and take a step up. Each of our troubles is a stepping stone. We can get out of the deepest wells【 by】 not stopping, never giving up, shaking it off, and taking a step up!
Remember the five simple rules to be happy:
1. Free your heart from hatred.
2. Free your mind from worries.
3. Trust in God.
4. Give more.
5. Expect less.

第三题，原句为：it just wasn't worth to retrieve the donkey是个错句! worth是个介词！ 考试英语要求改为：worthwhile
本题改为：It just wasn't worth it to save the donkey.
第一个it是形式主语，真主是to save the donkey这个不定式所表示的这一件事情。
worth是介词，和及物动词一样，后跟名词或代词（作介词的宾语）腔握清，这worth后的it叫形式宾语。类似的：I hate it when people ask me for money. 中的it.说它指代什么，只可意会，不可言传。你懂皮漏的！！！

这最后一空，填by, 一是原文如此。二是原作者想表达的意思是：只要通过。。。，靠着。。。，就能。。。，所以用by. 三、buy 是介词，后跟动名词的否定式not doing sth. and never doing sth.

你用if,是连词，一般跟从句，表示”如果。。。“，用在这里不是很好：
1. 前面有个just ，见过even if, 没见过only if, 没见过just if
2. 有if necessary, 等等if 从句省略主+be的情况。这里你想说是=if you are not stopping and are never giving up吗？ 如果用if从句，则不用现在进行时，要说：If you don't stop and never give up, 放入也行，但不能省略you do.

3.it是形式主语，指代内容是to save the donkey，翻译过来：不值得去救一头驴。
anything很明显没有理由填在这。
410.by doing sth通过历斗做什么事，固定搭配，在此翻译为：通过不放弃。

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