During the period of catch fire,many people tried hard to protect their personal items,even through it was uesless.
參考答案:through----though
uesless---useless
前面的时间状语从句也不太好建议改成 when的从句 ]
主句 many去掉 personal items---own possession
让步从句去掉 改成even those useless。之类
when there is a fire people try hard to protect their own possession, even those they don't need at all.