the first textbook written for teaching english as a foreign language came out in the 16th century.

问题描述:

the first textbook written for teaching english as a foreign language came out in the 16th century.
为什么teach 要用动名词啊?还有为什么用 written for

the first textbook written (被写的= which was written)for(表示目的,为了) teaching(动词作定语,修饰English,意思为教学的) English as(当做) a foreign language came out in the 16th century