The letters are like two letter sounds in English.

If you want a letter to sound official, split an infinitive.

Your letter sounded as if you thought she needed help.

Your letters sound like y'all are doing real well.

The letter sounds very much like the speeches the Mayor regularly gives to business groups.

Her letter didn't sound as though she was.

The letter sounded more like a love letter than a dear John.

As you say, the letter, on the face of it, sounds genuine enough.

That letter almost sounds like we us around this table are expected to choose some of the sites.

They are responsible for determining what a symbol, or letter of the alphabet, sounds like.