书城教材教辅科学读本(英文原版)(套装1-6册)
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第125章 第二册(42)

Maize is also called Indian Corn. The plant is a great tall grass, with a hollow, jointed stem, and long pointed leaves. The ear is called a cob. It contains a great number of large grains, set close together. Maize grows in warm lands. It contains very little gluten. The starchy part of the grain is made into corn- ?our.

About Metals

"Look at this knife, Norah," said Fred. "Do you know what it is made of ?""It is made of steel," said Norah.

"Quite right," said Fred. "See what a bright polished surface it has. When it gets dirty what must we do?" "We must rub it," said Norah. "That will polish itagain. The more we rub the brighter it will shine." "Right," said Fred. "Now, look at the copper kettleon the hob. That, too, is very bright. How is it kept bright?""It must be rubbed like the knife, and so must the tins that hang in the kitchen. They always look bright.""Teacher gave us a new name for this brightness of the metals," said Fred. "He calls it lustre. You must learn to say that these bright-shining metals are lustrous-full of lustre or brightness.