'No; he has a latchkey, and he let himself in.'

'实在不知道。他有把的钥匙，他自己开门进来的。'

There was a spring lock on the door.

门上有把。

That latch is a bit stubborn, but I'll take care of it.

那道很难理 但理好的。

It was close upon twelve before I heard the sharp sound of his latchkey.

将近十二点钟，才听到福尔摩斯用钥匙打开大门上的声音。

Pressing here and there, it only took him a moment to discover a latch inside the back.

到按了按，他很快就发现后面有个。

But according to Sam, there's like this swing bar lock, like a door latch secured from the inside.

但据萨姆所述，门上装有个类似门闩的，从内部将门反。