You wouldn't see that on the test. To be clear, you'd have to use "first blah blah blah and then blah blah and finally blah" or something similar to delineate three separate timeframes.e.g. E1 = Mary completed her work. ( The first completed event)
E2 = Mary went to play tennis.(The second completed event)
E3 = Her mother arrived.(The third completed event)
You might see something like: 2 events happened simultaneously and then some third event happened later.
When the teacher came back to the classrom, she thought that the boys had been studying but the girls had been goofing off.
Or 1 event happened and then two others happened simultaneously and later.
One teacher thought that Jimmy had cheated on the exam but the other believed his protestations of innocence.