1. I will buy that game because my parents may give me some money
I ? (can, buy) that game if my parents ? (give) me some money.
2. I won't buy that game because my parents won't give me any money
I ? (buy) that game if my parents ? (give) me some money.
3. I didn't buy that game because my parents didn't give me any money
I ? (buy) that game if my parents ? (give) me some money.
4. He was driving very fast, so he had an accident.
If he (drive ) very fast, he (have) an accident.
5. I can't help you, because I don't know English.
I (help) you if I (know)English.