no question is a dumb question, just ask. but if you don't have any questions, you were probably not listening. a programmer must be as good a listener as a speaker. you should listen and see beyond the words, often one word packs a lot of assumptions and context which needs clarification.
avoid multitasking while in meetings and while talking to people. this helps understand the topic at hand better. pay attention to each word, build mental model of what's being said. reading good books and participating in deep conversations and then backtracking and avoiding fast paced content helps improve the listening.