IF you have students that aren’t very confident or happy about speaking, this is a good idea that always works for me.
The first thing I do is to write a dialogue of about six or eight sentences on the blackboard and then I drill it. I get the whole class to repeat each line after me a number of times until they sound very natural.
Then once we’ve been through this dialogue a few times I begin to erase a few of the words from each line. Then we go through the dialogue again, this time with the class trying to remember the complete lines without me prompting them. Then we drill it again without those words.
Finally, we end up with more and more of it being rubbed off until we have the dialogue with just perhaps one or two words in each line as prompts. Then all the students try to say it all together. The final practice could be done in pairs and the students should then write the dialogue down.