- I would like to present the results of [experiment].
- I would like to lead a group discussion about the implications of [novel hypothesis].
- I would like to teach you how to perform [new calculation].
- I would like to tell everyone how to comply with [complex new regulations].
Sometimes a picture is worth a thousand words. I've been at very productive scientific meetings where someone puts up one or two slides of data and we spend the rest of the time in an open discussion around the whiteboard trying to figure out what it means (and which experiments should come next).