Mutiple fill in the blanks on one slide?

You can make this more helpful to the student too by adding a tick/cross object next to each of the text entry fields that is triggered to identify which ones they got wrong.  A much better experience for the student. You can also make only the incorrect ones reset if you want to allow them to carry on and get the question correct (with unlimited attempts). Simply add the required triggers to the continue button on the feedback layer or create your own custom feedback layer.