题目

We could see that he was trying to _____ his own responsibility for the delay, instead of accepting his fault.         A. run over           B. smooth over     C. pass off     D. turn down 答案：B 解析: smooth over(=make smooth, put right, balliate)使平息，使恢复正常的，掩饰：1)I will try to smooth their quarrel over.(我将设法平息他们的争吵。) 2)Don't try to smooth over your fault.（不要设法掩饰你的过错。）一复色光中只含有a、b两种单色光，在真空中a光的波长大于b光的波长．①在真空中，a光的速度__________(填“大于”“等于”或“小于”)b光的速度．②若用此复色光通过半圆形玻璃砖且经圆心O射向空气时，下列四个光路图中可能符合实际情况的是__________．