知M、N是两个集合且M∩N=M，则有（ ）
A．M⊇N
B．M⊆N
C．M⊋N
D．M⊊N
∵M∩N=M，
∴M⊆N．
故选B
Everybody needs calcium, but it is quite possible for a similar person to be totally healthy by eating only________.
A．as half much
B．as much half
C．half as much as
D．half as much
慢性风心病主要死因
A．脑出血B．心律失常C．心力衰竭D．心源性休克E．尿毒症
