181. Be careful! The water is too hot. You'd better ___C___ it right now. A. do not drink B. not to drink C. not drink D. not drinking 【考点】 You'd better 为You had better的缩略式。sb had better (not) do sth为一常用句型，意为"某人最好(不)去做某事"，请大家务必关注其否定结构。
182. We found ___A____ necessary to protect the environment. A. it B. this C. that D. what
【考点】 "主语+find+ it +adj. + to do sth"为一常用句型，意为"某人发现做某事……"，其中it为形式宾语(此时不可用this/that/one等代词替换)，真实的宾语为后置的不定式短语。
183..中文：从战争开始时他就一直在那里工作。(误)He has worked there since the war has begun.
(正)He has worked there since the war began.（since引导的从句表示过去的某时间点，应用一般过去时。）
184. 中文：他去年离开家我就一直没有见过他。(误)He left home last year and I did not see him since.
(正)He left home last year and I haven\'t seen him since.（since后面省去的是he left home last year，前面的句子要用完成时。）
185. 中文：我去看他们的时候他们在吃晚餐。(误)They had supper when I went to see them.
(正)They were having supper when I went to see them.（他们在吃晚餐是在过去我去看他们的时间某一点上正进行的动作，应用过去进行时。）
中文：她两个月前去澳洲了，她许多年前到过那里。(误)She went to Australia two months ago. She has been there many years before.(正)She went to Australia two months ago. She had been there many years before.（many years before是从过去的某时之前算起的，表示过去的过去，要和过去完成时连用。）
186.Neither he nor you is good at English.（×）Neither he nor you are good at English.（√）
析：either... or...，neither... nor...，not only...，but also...等词组连接句子的两个主语时，谓语动词遵循"就近一致原则"，即由靠近谓语的那个主语决定谓语的人称和数用何种形式。
187. I can't help _____ the house this afternoon A. sweeping B. sweep C. swept D. with sweep
B。易错选A，学生误用了短语can't help v-ing。但此题不是"忍不住"之意，而是"不能帮……"之意。
188.The lift is used to ____ up and down every day.A. going B. went C. go D. gone
C．易错选A，学生是根据短语be used to v-ing（习惯于…）做出的选择。但此题的be used to是被动语态，不是"习惯于…"而是"被用来做……"。
189. My pen ____ better than yours. I may lend it to you.A. is written B. wrote C. writes D. is writing
C。易错选A，学生认为"物"作主语时，应用被动语态。但此句中并不是pen"被写"，不能用被动形式。
190.____ my visit to France, I arrived ____Paris the first. A. At, in B. On, at C. During, to D. In, on
B。易错选A，学生的根据是巴黎是大地方所以应用介词in。但根据此题之意，巴黎是"我"访问法国的第一站而非目的地。在"我"的访问的行程中，巴黎只是旅途中的一个"点"，故宜用at。