Gasp

I've noticed lately that when Ethiopians are listening to someone's
opinion and want to give a sign of agreement without actually
interrupting the other person, they will make a gasping sound, slowly
taking air into their slightly open mouth. It is not unlike the sound
someone might make when startled, but slower, drawn-out and relaxed.
Although it's not something I have started doing myself (yet), I can
imagine this to be one of those things you would pick up without
realizing it after living here for a while. It is as if they are taking
in what you are saying, deep into their lungs and holding it there for a
short moment of consideration, and then they nod their head or say
something in agreement.