Do you ever have one of those classes where you are asking questions but you get better more response from the wall than you do from your students?
If you find yourself in this position next time you could try what I do. This works best for younger students and almost certainly not with adults!!
If i have asked the class the same question about 362 times and still no response i have everyone stand up. Then have one person start walking around the class and the rest of the class forms a line and follows them. then i have that first student speed up a bit so they aren't just slouching around. Then i ask my question again. As soon as one student answers the question (right or wrong) they can sit down. Quite quickly you will have received a verbal response from everyone in the room. After that the students respond much more quickly to my questions.
Variation
if the question you are asking can have more than one answer, don't let the students repeat what another student has said.
I hope this works for you