根据句意填写单词补全句子。
1. Beijing is the _____________ city of China.
2. I live in China, I speak _____________.
3. The U. S. is _____________ of Canada.
4. Tom lives in the U. S. He speaks _____________.
5. Canada's flag _____________ a leaf.
6. What _____________ is the flag of China? It's red.
7. How many stars in the China's flag? There are _____________ stars.
