You've got the wrong number.
你打錯(cuò)了。
You've got the wrong extension.
你打錯(cuò)分機(jī)了。
This is a private number.
這里是私人住家(電話)。
There's no Frank Smith here.
這里沒(méi)有Frank Smith這個(gè)人。
Is this 23941666?
這里是23941666嗎?
Let me put you through.
我?guī)湍憬舆^(guò)去。