My mother likes volleyball. She thinks (认为) it is _______.

Linda’s father isn’t an engineer. Her mother isn’t an engineer, ______ .

If he _____ with us, we _____ finish the task earlier last time.[ ]

______ in his studies, he didn’t know that all the others had left.

Do you know ______ this i-pad belongs to? —Let me see. Oh, it’s ______.