He had left I could say hello to him. [ ]
A. before
B. when
C. after
D. until
答案:A
A.激光通信不受气候条件的影响
B.激光束不能载有图象信号
C.激光的颜色很纯
D.激光通信和无线电通信完全不同
舌红绛而光者,属()
A.阴虚
B.气虚
C.血虚
D.气阴两虚
E.水涸火炎