Sky safety system _________ everyone from crashing.

Could you help me to send this letter to my boss?

I'm afraid I _________ part in your party this weekend.

 _________ to Australia on your summer vacation next year?

Is this yours bicycle or hers?

I hope pollution _________ worse next year.

I want to visit a beautiful beach in Viet Nam. Could you suggest one?

Next year, we _________ and get jobs.

What problems do you think future transport _________?

There are many places worth seeing in London.

I'm not sure I _________ travelling by hot-air balloon again or not.

Mary went to Viet Nam last year and it was her second time.

Yesterday we decided to paddle around West Lake in a canoe.

 _________ use my jetpack to fly anywhere easily.

They won't come to the stadium by their car.