Inspect the code carefully for this project. Make sure you understand what each block does and why the costumes for the speech bubble sprite are in the order they are in and why the project begins with the last costume. Once you understand all that, then you should be able to make the following alterations.
Remix the project and add two new people. Give each person two turns in the conversation. Your conversation must be original and each turn must have a minimum of five words. The key problem which will be most confusing is figuring out how to position the speech bubble for the two additional people.