题目内容：

【 】 from his parents for a long time he was worried about them
A not hearing B heard not D not heard 这三个选项哪里错了

优质解答

三个都有语法错误,
这个句子需要定语形容词
正确的形式是
not having heard from his parents ...
这种 “因-果”句型叙述的“因” （没获得父母的信息）已结束,
例句：
having eaten,I feel full
not having eaten,I feel hungry