请问句中的be动词为什么要用原型?
问题描述：
请问句中的be动词为什么要用原型?
Within weeks Matthews was letting it be known that he would appreciate aninvitation to meet the Prime Minister at Downing Street.
句中的letting be known that为什么要用be动词原型,还有appreciate 在句中是什么呢意思?
答
let sb.do sth..
欣赏,感激.