[who, whom, that, which, whose ]
1.—Could you help me find such a boy
is tall and kind? —Sure.I think Jack is the one
you are looking for.
2.—I have a good friend
eyes are bule. She is from America. —Really? Could you introduce her to me?
3.The poor girl
sells matches（火柴）can't find a warm house
she can live in,so that she is dead on a cold night.
4.I don't know anyone here.because I'm one person
arrives here the first time.
5.“Why don't you give back the pen
color is red to me? I need it now.”“Sorry. I will.”