They        have arrived at lunchtime, but their flight was delayed.

Eye doctors recommend that a child’s first eye exam____ at the age of six months old.

---Did you get a ticket? ---Yes. Otherwise I____ the concert last night.

       for the free tickets,I would not have gone to the film so often.

It is written clearly in the requirements that all passengers ______ check onto board 30 minutes before the plane takes off.