If you're struggling with how to design an exam language, look back at the notes from the "Introduction to Languages" lecture: they discuss how a language consists of data, operations on the data, and control commands for ordering operations. What are each of these for an exam program? Imagine that the teacher were verbally giving commands to the exam software saying how to give the exam. The commands (verbs) that you imagine the teacher issuing are the commands/operators in your language; the nouns are the data.
Once you've identified the operations and data, see how to organize them. If some data are similar in spirit but different in details, make a multi-case data definition (like we did for animals).