_______ is part of children’s nature. They always insist on getting to the bottom of everything.

Hey, Jack! I’ve worked on this math problem half an hour ,but it’s got me nowhere. Could you give me a hand – ______ . I’m good at math.

Shall we go out for a trip after the mid-term exam—___________. It’s a good way to rest.

Is that __________ hat—No, it’s not ____________. It’s ______________.

Could I use your computer —Sorry. I am _____ it.