To complete an assignment, choose a reference for the left side. This reference will be made to point to some object instance.

Then choose an object instance from the right list. You can also choose to set the reference to be null by choosing that option. Finally, you may define a new robot instance or a new simple (non-robot) for the right side by choosing "new". A dialog will let you fill in the required specifications of the new object.

You are responsible for choosing an object (right side) that is compatible with the reference on the left side.