Well, the original question has only three options:I wouldn't use either.
We were supposed to/scheduled to have a PE class now, but...
We must/ We should/ We shouldn’t have a PE lesson now, but our PE teacher’s ill so it’s been cancelled.
Where's the "original question" from?Well, the original question has only three options:
A quiz I found online.Where's the "original question" from?
If those are the three options, "should" seems the most likely. "Must" is wrong, and "shouldn't" wouldn't make sense in the context.
The page you linked to doesn't show that question. Maybe it occurs later in the exercise but it appears you have to become a member to see more.A quiz I found online.
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