书城教材教辅科学读本(英文原版)(套装1-6册)
47723000000227

第227章 第三册(52)

"The largest of them, the ostrich, is often seven feet high. They all have powerful legs for running, but as they do not fly, they have no use for wings. The wings are always very small. The foot has only two short thick toes. It is meant to be a solid support for the runner."SUMMARY

Climbing-birds have two toes in front and two behind. They live entirely in the trees. The scratchers have strong, blunt claws for scratching in the ground to ?nd their food. The waders have long, stilt-like legs, for walking in the water. Their long necks and bills are to enable them to reach their prey in the water. The feet of all swimming-birds are webbed. The runners have long legs, and short, thick, solid toes.

Lesson 17

Solid Water

"Look what I have got to show you." said Fred, as he came in from school.

"Why, it is a lump of ice," said Norah, "What are you going to do with that, Fred?""I am going to try and teach you something about the ice, as teacher taught us in our lesson this morning. I"m going to be teacher tonight," said Fred.