Through thick and thin, they have always been my precious team mates, advisers, and above all, friends.
我们同甘共苦,亲如伙伴,他们是我的军师,更是我的朋友。
This would solve the problem of ventilation, for if a train entered this tunnel, it would draw in fresh air behind it.
因为如果有列火车开进隧道,它就把新鲜空气随之抽进了隧道。