is on their mother's back. 就是爬到母亲的背上

233. Her tadpoles are in mortal danger.
     它的蝌蚪危在旦夕
234. Their tiny puddle, almost dry.
     小水洼几乎快要干涸
235. Their only means of escape
     唯一的逃生方法
236. is on their mother's back.
     就是爬到母亲的背上
237. The hard part is finding water.
     难点在于找到水
238. Luckily...
     幸运的是
239. ...she knows exactly where to go.
     它知道该去哪里

来自《我们星球上的生命 第一季 第三集 Life on Our Planet S01E03 入侵大地》第 236 行