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New words text Think about it Let’s do it explanations New words ?sunlight n. 陽光 ?feed v. 喂養(yǎng) ?billion n. 十億 Think about it ? How many plants do you think there are in the world? ? How many plants can you name? ? Why do plants have flowers? How many parts do plants have? ? A plant has four parts: flowers, leaves and stem grow above ground. Roots grow below ground. What do root do? ? Roots bring water from the ground to the plant. What is the stem for? ? The stem carries the water from the roots to the leaves and flowers. ? The stem holds the leaves and flowers in the sunlight. ? Leaves make food for the plant. Why do plants have flowers? ? Is it because flowers are beautiful? No! plants have flowers because the flowers make seeds. New plants grow from seed. What part do we eat? ? People eat all parts of a plant. ? A carrot is root ? We eat the leaves of cabbage. ? The seed of the rice p