（1）It was not _____________he saw his mother that he realized how old she had become.
（2）Sometimes I wish I_____________(live) in a different time and a different place.
（3）The area has been badly _____________(affect) by pollution.
（4）He went back to the office____________he had left his keys.
（5）Today, we will begin_________we stopped yesterday so that no point will be left out.
（6）He was about to leave _____________the bell rang.
（7）I didn’t see your sister at the meeting. If she ______________(come), she would have met my brother.
（8）The man ___________talked to you just now is an engineer.
（9）He suggested that we ____________(leave) before sunset.
（10）The reason _________they have succeeded is that they are strict with themselves.