I
1.D
2.A
3.D
4D
II
1.C
2.B
3.C
4.A
III
1.will visit
2. Reads
3. have ever read
4. Will be able to teach
IV
1.Unless I leave now, i will miss the train
2. It is very easy to learning how to use a computer
3.My grandmother is the oldest in my family
4. Tom has played football for 4 years