--- Shall we go out for a walk?--- Sorry. This is not the right _____ to invite me. I am not in the mood to walk now.
I have many friends,some are teachers.
The plane ________ when I arrived at the airport.
_____ is a possibility _____ Tom will get first place in the long jump.
He is ________ experienced teacher in our school.
At present, you do meet with some difficulty in English learning, but you will have a good knowledge of it.