Please, help me. If he (be) my friend, I

Please, help me.
If he (be) my friend, I (invite) him to the party.
If I (be) taller, I (become) a basketball player.
If an asteroid (hit) our planet, it (cause) an ice age.
John (travel) around the world if he (win) a lottery prize.
We (go) to Spain this winter if we (have) enough money.
She (not mind) if you (borrow) her car.
If you (move) to another city, I (phone) you every day.
They (laugh) at me if I (sing) this song.
If we (have) free time, we (start) a new hobby.
If I (know) her secret, I (not tell) it to anyone.