hear意思是听到,指听到的结果.如I heard her singing in the classroom.我听到她正在教室里唱歌 hear of.的意思是听说.如I have never heard of him before.我以前从来没有听说过他 because 和because of的意思都一样,不过用法不同.because为连词,后面跟句子.而because of后面一般跟短语.如： Because he failed in the exam,he was punished by his father Because his failing in ghe exam ,he was punished by his father 两句话都是同样的意思,都是因为他考试没及格,他被他父亲惩罚了.
