看地图，选出合适的单词填空完成句子。
1. China is the east of _______________ (the U. S. / the U. K.).
2. The U. S. is east of _______________ (Canada / China).
3. Canada is north of _______________ (the U. K. / the U. S.).
4. Australia is south of _______________ (China / the U. K.).
