在船舶火灾中人员死亡的原因主要是：
A、烧伤
B、外伤
C、窒息和中毒
D、盲目行动
参考答案：C
不包含交换设备的网络是（）。
A、分组网
B、帧中继网
C、DDN
D、以上都不是
— Don't you think Jim was brave to go bungee jumping?
— Personally, I thought he was ________ brave. [ ]
A. more mad than
B. as mad as
C. mad more than
D. too mad as
