Sorry, I don’t know the answer ______ the question ______ it is too hard. [ ]

What’s the low-carbon(碳) life style like?—-Save energy, produce carbon.

There is a ticket on the floor, is it yours? —Oh, yes, it’s mine. —Let me _____for you.

My bag is different _____ yours, but it is the same _____ hers.[ ]

. —Did you get there by ______ bike?—No, I took ______ taxi.