带firm的单词有哪些

单词有confirm确认， firmer坚硬的，坚固的， firmness坚固，例如：

1.All telephone reservations must be confirmed in writing.所有的电话预订必须以书面形式确认。

2.Flights should be confirmed 48 hours before departure.航班应在起飞前48小时予以确认。

3.It has been confirmed that the meeting will take place next week.已经确定会议将于下个星期召开。