写作时如何区别such as和for example？

such as是介词，后跟名词或动名词；for example是副词短语，后可用词、短语或句子。另外，for example用在句中时前后都要有逗号。

例：

1. But unlike books such as Harry Potter, His Dark Materials explores deeper and darker moral territory. 不像哈利波特这样的书，His Dark Materials探索更深更阴暗的道德领域。 (BBC)

2. In 1910, for example, nearly 15% of people in the U.S. were born in another country. 例如，在1910年，接近15%的美国人出生在别的国家。（CNN）