位于上颌骨的是
A. 关节突
B. 关节窝
C. 翼腭窝
D. 翼肌窝
E. 尖牙窝
Without a passport, leaving the country is ().
A. in question
B. without question
C. out of the question
D. out of question
There is an abundant supply of cheap labor in this country.
A. a steady
B. a plentiful
C. an extra D. a stable
唾液的主要成分中不包括
A. 黏液
B. 白蛋白
C. 唾液淀粉酶、麦芽糖酶
D. 黏蛋白、溶菌酶
E. 钾、钠、钙、镁
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