椎动脉发自（）
A.升主动脉
B.颈总动脉
C.颈外动脉
D.锁骨下动脉
E.颈内动脉
参考答案：D
Rather than _________for the love of music, nowadays more and more singers attach great importance to _________rich and famous by singing.
A．sing；becoming
B．sing；become
C．to sing；become
D．to sing； becoming
如果两邻居相互为对方铲除门前积雪，并为此向对方付费，他们的行为对GDP将不会产生影响.（）
