87.　　He knew France well, as if he had been there many times。

　　(似乎他多次去過(guò)那個(gè)國(guó)家)

　　88.　　Seeing those pictures, the student couldn't help thinking of those memorabledays. (回憶起那些難忘的日子)

　　89.　　Only after they had performed hundreds of experiments, did they succeedin solving the problem. (他們才成功地解決了這個(gè)問(wèn)題)

　　90. 　　Some people hold the mistaken belief that our domestic products

　　are always inferior to imported goods. (總是次于進(jìn)口商品)

　　91. sometimes giving up is helpful for you to concentrate time and energ on(有助于你把時(shí)間和精力集中于) a few things that are truly important。