— To my disappointment, the experiment was ______ complete failure.

— Don't lost ______ heart, John. Failure is the mother of success.[ ]

A. /; /          

B. /; the        

C. a; /        

D. a; the

不属于茎突后间隙的是（）

A.迷走神经

B.下颌神经

C.颈内静脉

D.颈交感干

E.颈内动脉