all of a sudden和immediately有什么区别?RT,希望可以举例说明,浅显易懂最佳.谢绝粘贴词义.

all of a sudden,If something happens all of a sudden,it happens quickly and unexpectedly.All of a sudden she didn't look sleepy any more.突然的意思（表示事出意外）immediately,If something happens imme...