题目内容：

The boy’s parents were very __ ___(thank) to the policeman because of his help.

优质解答

The boy’s parents were very __ ___(thank) to the policeman because of his help.
答案：thankful,整句话的意思为这个男孩的父母因为警察的帮助非常感谢他.也可翻译成“这个男孩的父母对于警察的帮助很感激”.