asking him to go to his home 是分词短语作非限制性定语,修饰a letter
可以改为:
He received a letter yesterday ,【which asked 】him to go to his home
asking him to go to his home 是分词短语作非限制性定语,修饰a letter
可以改为:
He received a letter yesterday ,【which asked 】him to go to his home