the old man look much older than before b____of his face
问题描述：
the old man look much older than before b____of his face
答
the old man look much older than before because_ of his face
因为他的脸,那位老人看起来比以前老了许多.
because of,因为,由于,后面接代词,名词,或动名词.
区别于because,后面接从句.