1.If he trained enough last year, he would be a first-class sportsmen now.
2.If the pupils are active they'll understand this difficult material.
3.If the pupils were attentive, they would understand the homework.
4.If the pupils didn't work hard, they wouldn't do well in their examinations.
5.If she was good at foreign languages, she would try to enter the foreign languages department.
6.If I have a toothache I'll go to the dentist.
7.If he went to the dentist to have his tooth filled, he wouldn't groan with pain now.
8.If she needs any treatment, she'll go to the polyclinic.