—Who______ it be that is knocking at the door? —It ______ be Father, but I’m not sure.
The teacher is so kind to us that we all ___ him as our good friend.Which of the following is not suitable?
I have warned him of the danger ___ but he always turns deaf to my warning every time.
He has ___ the company ___ the post for three times, but he has been ___ three times.
She squeezed the water ___ her wet clothes.
Can’t you think that a dictionary is an important ___ in learning a second language?