• Cross three chasms过三道沟
• This chasm眼下这道沟
• Open the gate开灯塔石门
• Light the lamp点亮灯塔

Three chasms ring the lighthouse, each with a bridge. There is one rule: a bridge exists only while its pressure plate is held, and whoever holds the plate cannot cross. One plate per bank — you stand on this side's, the companion crosses; it stands on the far one, and your feet are free. All three chasms work this way. The lighthouse is enclosed by a stone wall whose only way in is the gate, and its rule is the inverse: the two plates outside it must be held at the same time for it to sink, and once open it stays open, so nobody is left behind. Then both of you walk inside the wall and the lamp lights. The companion cannot see whether a plate is lit and has to ask through its tools. For company, have it summon a few villagers.灯塔外面有三道沟，每道沟上都有一座桥。规则只有一条： 桥只在承重板被压住的时候才在，而压着板的人自己过不去。 两岸各一块板——你踩住这边的，同伴过去；它踩住对岸那块，你才腾得出脚。 三道沟都是这个。 灯塔围在一圈石墙里，唯一的入口是石门——它的规则正好反过来： 门外两块板必须同时压住，门才沉下去，而且开了就永久开着，谁都不用留下。 然后两个人一起走进墙里，灯才亮。 同伴看不见板亮没亮，得靠工具问。想热闹一点，可以让它造几个村民陪着。