受要约人认为要约中有些内容不能接受,并提出修改意见,称为()。
A.要约
B.邀请要约
C.反要约
D.承诺
参考答案:C
Friendship can't be ________in terms of money but money is an effective means to ______ how
strong the friendship is. [ ]
A. measured; test
B. weighed; weigh
C. measured; measure
D. tested; measure
具有良好时间分辨力的超声心动图是()
A.二维超声心动图
B.频谱多普勒超声心动图
C.彩色多普勒超声心动图
D.M型超声心动图
E.组织多普勒显像