1、I left my umbrella in my room。Could you wait ----I go back to it? A when B if C while D before 选择C. while连接的两个动作可表示同时进行.2、The old lady ----。She ----for five months。 A dided,has been died B died,has died C dies,has died D has died,has been dead 选择D. have been dead后接时间段,表示"已经死了多长时间了"3、你能控制下声音吗? Can you ---------your voice? 应该是:control