The reason why I have to go is _____ if I don’t

I didn’t see you when I went to your office yesterday afternoon. Where were you—I ____ a meeting in the meeting room.

_______ the road round to the right and you’ll find his house

Don’t interrupt meI ________ letters all morning and have only finished five

While playing ping-pong, our eyes see the ball coming, judge its speed and then hit it back ________ it should go.