改错练习

1. Human being have thirty-three or thirty-four vertebrae，but a snake may have as many as three hundred.(1)____
译文：人类有33或者34根椎骨，但蛇可能有多达300根椎骨。
2. Over the past two decades, the popularity of the bicycle as a mean of transportation and recreation has increased tremendously in the United States.(2)____
译文：过去的二十年间，自行车作为一种交通和娱乐工具在美国大肆风行。
3. He was only one of the candidates who was going to take the oral defense.(3)____
译文：他只是即将进行口头辩护的候选人之一。
4. For convenience it is common to speak of plants as "herbs," "shrubs," and "trees," but it is really no sharp distinctions among them.(4)____
译文：出于方便人们通常把植物说成草、灌木和树，但其实它们之间没有明显区别。
答案解析
1．分析：being→beings。考查数的一致。谓语动词为have，且Human being前并没有表示单数的不定冠词a，说明主语不是第三人称单数而是复数，应改为beings。
2．分析：mean→means。考查名词辨析。mean作名词，表示“中间；平均数”，用于此不符合句意。此处表示“方法，手段，工具”，应该用以s结尾的名词means。
3．分析：(who) was→were。考查单复数。确定从句中动词单复数形式的关键是先行词，这句话的意思是他只不过是将参加辩护的候选人中的一个，先行词是the candidates，而不足one，所以定语从句的谓语动词要用复数were。但这句：He was the only one of the candidates who was going to take the oral defense.中，由于有定冠词the限制，先行词是one，则要用was，这是有无定冠词的区别。
4．分析：it→there。考查there be句型。此处it并不代指句中任何成分，也不是形式主语，因为后文并无真正的主语部分，故it应改为there。