There's no sense in going by boat when the plane is just as cheap and much quicker.
既然乘飞机和坐船一样便宜而且还快得多,那么就没有理由去坐船。
There was less food for birds and also for the prairie dog, a kind of animal which lives in holes in the ground.
供鸟类吃的食物少了,供草原犬鼠(一种生活在地洞里的动物)吃的食物也少了。