Parents complain their children are behaving unreasonably _____children consider their parents to be old-fashioned.
Many teenagers say that _____ they have a lot of friends, they really have no best friend.
As we know, penicillin became the greatest drug of the 20th century, ______ millions of lives.
—How long _______ in Shanghai?—I will be there attending a conference and giving a speech, which will take about 3 days.
If he _______ the opportunity at that time, he would be the new department manager now.
To everyone’s amazement now, technology ________ faster than most people can keep pace with.