关于 at a meeting 的用法见得比较多，但很少见到有 in a meeting 的用法，比如下面一句：
She is in a meeting now, but I will let you know as soon as she is free.
请问 in a meeting 与 at a meeting 的区别是什么？谢谢！
向尊敬的曹老师请教几个长难句1、He was directly invited to join their party, but he declined it, observing that he could imagine but two motives for their choosing to walk up and down the room together, with either of which motives his joining them would interfere.问题1：请教曹...
plaster is a whitish kind of paste, a mixture of lime, water and sand. 来自托福听力材料请问a kind of 属于限定词（例如，a the my）还是属于 美小圆...木书房中的某一种？为什么？如果属于限定词，无疑是 a kind of whitish paste 更符号常用语序...
It's uncertain whether the experiment is worth doing 为什么不能用if？既然老师们之前说过在形式主语的主语从句中if/whether都可以，那为什么这里很多选择题答案里面既有if也有whether却只能选whether? be
uncertain 后面用whether 的情况网上很多说...
...cated to the south of the equator, below many other countries on the glob, it's often informally referred to as "down under".教辅上给的注释是located...是形容词短语作状语。此处能不能理解为located...为过去分词短语作状语？什么时候分词可以理解为形容词...
...is wrong.变为一般疑问句时，不能使用外置结构：不能说：It is wrong what I have said.例句2：Where Covid-19 virus comes from is not clear.变为一般疑问句时，可以使用外置结构：Is it clear where Covid-19 virus comes from is not clear.问题：请教曹老师，这...