1-to buy
2-to do
3-smoking
4-flying
5-writing
6-to do
7-making
8-to be
9-building
10-to see
II.
1-If I study, I will pass the exams.
2- If the sun shines, we will walk to the town
3-If he has a temperature, he will see the doctor.
4- If my friends come, I will be very happy.
5-If she earns a lot of money, she will fly to New York.
6-If we travel to London, we will visit the museums.
7-If you wear sandals in the mountains, you will slip on the rocks.
8.-If Giang forgets her homework, the teacher will give her a low mark.
9- If they go to the disco, they can listen to loud music.
10- If you wait a minute, I will ask my parents.