In the case of makeup, it is a compound noun made up of the verb (make) and the preposition (up). There are no definitive rules about when to use a hyphen (make-up), nothing (makeup), or a space (make up) with compound nouns.
The best thing to do is use your spellchecker to determine whether the one-word version is a spelling mistake.
Make-ups will be allowed each semester for EXCUSED absences only.
Written make-ups may be assigned by the teacher for injured students.
1) You may physically make up a class missed, by attending another class during your scheduled lunch, study hall, or by staying after school.
Make Up Assignment
If you are making up a class with this option you must make arrangements with your teacher ahead of time.
However, I recognize that sometimes “life happens.” In these instances, you may use your allotted two flex days.
These days allow you to submit an assignment up to two days late without penalty.
Phrasal verbs are never merged into one word or joined with hyphens.
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