51、We should learn from those are ready to help others.
A.who B.whom C.whose D.they
52、I have two brothers, are doctors.
A.both of them B.both of who C.both of whom D.both of they
53、 everybody knows, China has the largest population in the world.
A.Which B.That C.As D.The thing
54、Everything can be done should be done.
A.which B.that C.all D.that
55、This is the house you saw the other day.
A.that B.where C.in which D.in that
51、A 52、C 53、C 54、B
55、A