快速作出反应。由谓语"will help"可知，此句缺少主语形式，且句中的"you"与动词"know"为逻辑上的主谓关系。故用动名词的一般形式作主语。

　　11．Shortly after suffering from a massive earthquake and __being reduced__ (reduce)to ruins，the city took on a new look.

　　解析：考查非谓语动词。句意：在遭受大规模的地震和损失之后不久，那个城市就呈现出了崭新的面貌。and为并列连词，连接after后的两个宾语suffering from...和being reduced to...。be reduced to (doing) sth.使沦为，固定结构。

　　12．China recently tightened its waters controls near the Huangyan Island to prevent Chinese fishing boats from __being attacked__ (attack) in the South China Sea.

　　解析：句意：中国最近加紧了对黄岩岛附近海域的控制以保护中国的渔船在南海海域不被袭击。prevent...from doing保护......免受......，根据句意可知"保护渔船不被袭击"，故from后为being done。

　　13．One learns a language by making mistakes and __correcting__ (correct)them.

　　解析：句意：人们在犯错误并改正它们的过程中学习一门语言。correcting them和making mistakes是并列的动名词短语，作介词by的宾语。

　　14．It's no use __complaining__ (complain)without taking action.

　　解析：句意：光抱怨而不采取任何行动是没用的。此句应为考查句型"It is no use doing sth."，此结构中需用动词－ing形式作真正的主语，it为形式主语。

　　15．I had great difficulty __(in)finding__ (find) the suitable food on the menu in that restaurant.

　　解析：句意：在那家餐厅，我花了很大力气才从菜谱上找到合适的食物。have difficulty(in)doing sth.为固定结构，意为做某事有困难。

　　Ⅲ.完成句子

　　1．Everyone __is satisfied with__ his performance.

　　大家对他的表演很满意。

2．I'd rather __have left a note__ on her desk.