若显微镜的油浸镜上的油已干，可用拭镜纸沾何物擦净，然后再用干净擦拭镜纸擦干净（）
A.清水
B.石蜡
C.无水乙醇
D.二甲苯
E.以上都不是
参考答案：C
Not a single word _____ when _____ about his late mother. [ ]
A. he said; asked
B. did he say; asked
C. he said; asking
D. did his say; asking
舌为何脏“之苗”（）
A.心
B.肝
C.肺
D.脾
E.肾
