87. You would not have failed if___(按照我的指令去做)

　　you had followed my instructions。

　　88. Despite the hardship he encountered, Mark never ___(放弃对知识的追求)

　　abandoned the pursuit of knowledge。

　　89. Scientists agree that it will be a long time before____(我们找到治愈癌症的方法)

　　we find the way to cure cancer。

　　90. Production has to be increased considerably to ___ . (与消费者不断增长的需求保持同步)

　　keep up with the constantly growing demands of consumers。

　　91. The more exercise you take, ____ 。(你越不大可能感冒)

　　the less likely you are to catch a cold。