In March he goes on a survival course and learns about the “umbles”: as hypothermia sets in you mumble, fumble, grumble, stumble, then finally tumble.

三月，外生存训练，懂得了寒冷下嘴、脚是么样：低温了，咕哝，摸爬，嘟囔，踉，仆倒在地。