The campaign has had a great influence on young people. A lot of them have stopped smoking.
The campaign has had a great influence on young people. A lot of them have stopped smoking.
A. So influential is the campaign that a lot of young people have stopped smoking.
B. But for the great influence of the campaign, a lot of young people would have stopped smoking.
C. Not until a lot of young people had stopped smoking did the campaign greatly influence them.
D. Only if the campaign greatly influenced young people would a lot of them stop smoking.