三叉神经痛的疼痛特点是反复短暂的_________疼痛，每次发作数秒到1～2分钟。
参考答案：发作性剧烈
It only __________ him 20 minutes __________ to his office every day.
A. takes; to drive
B. took; drive
C. takes; drive
D takes took
可以纠错的差错控制编码为（）。
A.奇偶监督码
B.二维奇偶监督码
C.汉明码
D.B和C
