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随时随地学习
随时随地学习
树(Tr)a tr has thr main parts, th roots, th branchs and th lavs. undr th ground, th roots sprad out so that th tr can stand firm. abov th ground, th roots form th trunk, and th trunk supports th branchs.nar th top of th tr, th trunk divids into branchs. at th top of th tr, th lavs grow out of th branchs. th lavs rciv sunlight to hlp th whol tr grow.
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