They say my dialogue is weak. What do I do?

Fiction writers often talk as if we have to write in two completely different modes: dialogue, and everything else. There is a basic difference: while narration is, clearly, the writer's choice of words to convey a story, dialogue is trying to evoke how people who are not the writer actually speak. If you've ever listened to recordings of real conversation - all ums and ers and going round in circles - you'll know that even the most naturalistic dialogue is in fact very different, and by no means all fiction-writers and playwrights - who deal chiefly in dialogue - are...