C2 长久地，长时间地
for a long time
George went on at great length about his various illnesses. 乔治滔滔不绝地讲起他身患的各种疾病。
He talked at length about his visits to various Roman sites.
The article deals at length with how to evaluate different sources of information.
She'll call her interior designer to discuss at length which lampshade to buy.
I'm a huge jazz fan and can go on about it at some length, given the chance.
formal终于，最终
If something happens at length, it happens after a long period of time.
At length, the authorities allowed her to go home. 当局终于允许她回家了。
At length, the suspect replied.
At length, all the obstacles were overcome and we were able to set off.
He waited anxiously until at length he spotted her entering the room.
At length, the two sides reached an agreement.
See also: length (TIME)