In Feb. ()came President Nixon’s historic visit to China.
A.1979
B.1972
C.1973
参考答案:B
The accuracy of scientific observation and calculations is always at the mercy of the scientist's timekeeping methods.
A.under the control of
B.within the kindness of
C.beyond the reach of
D.out of the control of
颌下三角内的有关重要结构在舌骨舌肌浅面自下而上的依次排序是()
A.舌下神经、颌下腺导管、舌神经
B.舌神经、颌下腺导管、舌下神经
C.舌下神经、舌神经、颌下腺导管
D.舌神经、舌下神经
E.颌下腺导管、舌神经、舌下神经