(A)根据句意及汉语提示,写出空白处单词的正确形式
1. We all know that it’s a bad manner to (乱扔垃圾)in public.
2. Many rivers are polluted and even the (底部)of the river is full of rubbish.
3. Let’s meet at the (大门)of the school at eight o’clock tomorrow morning.
4. The (主席)of this country, has paid many official visits to foreign countries since he took power.
5. Her (作品)of art are very popular with young people in China.

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