书城教材教辅科学读本(英文原版)(套装1-6册)
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第70章 第一册(70)

"Now look at this lily leaf. Hold it up to the light.

Do you see veins crossing each other in this leaf ?" "I can see the veins," said Norah, "but they runside by side, from one end of the leaf to the other." "Teacher says," added Fred, "that leaves of thiskind have parallel veins, and this means that the veins run side by side, as you told me, Norah."SUMMARY

A leaf consists of a blade and a footstalk. In most leaves ribs stretch across the blade, and veins spread over it in every direction. We call these net-veined leaves. In some leaves the veins run side by side. These are called parallel veined leaves.

Lesson 35

Coal-The Mine

"Can you tell me, Fred,"asked his sister a few days after, "how the men get the coal out of the mines in the ground?""I"ll try," said Fred. "That"s just what our lesson was about this morning.