How ______ is it from the railway station to the museum?

—What time do we have to be at the gate of the museum?  —______ the visitors begin to check in.

— Oh, really? Can Doris read through it in such a short time?— She covered the English novel ______ it took me, still less a simple story．

He was __ twenty when he was gone.

The boy knocked down by the car stood up all by himself , _____unhurt.