Active listening is an important part of any conversation in English. You should respond to what somebody is saying buy nodding your head, making sounds of approval or interest and using expressions like: Really?; How interesting!; I see.; That's incredible/unbelievable. This is one of the hardest things for Czech people when having a conversation in English as it's not common in our language. What's more, we take it as interrupting people; we're taught to stay silent if somebody else is speaking. On the other hand, it makes English-speaking people nervous if you're silent and don't respond. They think you aren't interested and/or fully engaged in the conversation with them.