路边放置的红色反光三角标志是什么意思?What does a reflectorised triangle placed on the side of the road mean?

路边放置的红色反光三角标志是什么意思?What does a reflectorised triangle placed on the side of the road mean?
前方有坏车或事故There's a breakdown or crash ahead
前方有道路施工There are roadworks ahead
前方路面有庆祝活动There's a special event ahead
前方有单车道桥梁,并且你没有优先通过权There's a one-way bridge ahead and you don't have the right of way

红色的反光三角标志表示车辆损坏停在前方或发生了事故,请降低车速。