A:cut i
B:cut dow
C:cut off
D:cut u
— Who ______ the girl from the fire?
— A kind-hearted young man, but he lost his life.
--- How long may I your bike?
--- For a week. But you mustn't it to others.
被俄罗斯人称为“母亲河”且能“五海通航”的河流是( )