When I listen to speech in a foreign language there is often a delay between my hearing of what is said and my understanding of it. My brain is working hard to separate the continuous stream of sound into words, and to work out the meanings of those words, though I don’t usually translate the words into English in my head, as that adds an extra delay. It’s a bit like the delays you get on some trans-Atlantic phone lines.
Such delays are not too much of a problem when listening to the radio or watching TV/films, but I tend to miss things because I’m trying to understand previous utterances. When talking to someone though, such delays make it appear that I don’t understand what they’re saying so they repeat themselves a lot or switch to English, while I’m frustrated because I know what they’re saying, but not immediately.
Practice should reduce and eventually eliminate these comprehension delays, with any luck. In the meantime, perhaps what I need are words or noises that indicate that I’ve heard what’s been said and am considering my response. The length of time you can remain silent after somebody has said something varies from culture to culture. In many cultures , people start to feel uncomfortable after a few seconds and feel the need to say something to fill the silence.
In Japanese you say hai! frequently to show you’re listening. If you do the same in English it can sound very rude – as if you want to other person to shut up so that you can say something.