观察舌苔的润燥，主要了解（）。
A.湿浊的消长
B.邪气的深浅
C.津液的盈亏
D.疾病的进退
E.胃气的盛衰
参考答案：C
On our arrival, we found Tom _____at the desk and ______a letter.
A．seated, wrote
B．sitting, written
C．seating, writing
D．seated, writing
按50：1的比例尺画图，一个零件画在图上是10厘米，这个零件的实际长是______厘米．
