长期全胃肠外营养治疗一般采用的置管途径是（）
A.股静脉
B.大隐静脉
C.贵要静脉
D.锁骨下静脉
E.小隐静脉
参考答案：D
We worked all night, _____ for the coming procession.
A．to prepare
B．preparing
C．prepared
D．was preparing
What are the implications of the statement "language is best taught when it is being used to transmit messages"
