— Is John coming by train ? — He should, but he ______ not. He likes driving his car. 

(2013·陕西高考)The children ________ lost in the woods; otherwise, they would have been at the lakeside camp as scheduled.

You are wet through. You ___________ in the rain.  

Your advice was a great help to us, without which all our efforts       .

.________ the warning message, more lives would have been lost in the flood.