because /biˈkɔz, biˈkɔ:z/ conj. 因为：We could not cross the river because the water had risen. 我们因水涨而不能渡江。I think it’s because you are doing too much. 我想是你做得太多的缘故。because of 因为：He was absent because of his headache.他因头痛缺席。