It is asking you to identify a suffix.
Let's practise

Tick which of the words have the same suffix.
appointed
appointment
ointment
point

- Read the question carefully and read it again. What is it asking you to do?
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- Remember that a suffix is added to the end of a word. Check the endings of the words for those that are the same.
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ment is the same ending on appointment and ointment
- Tick the words.
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appointment
ointment
- Check that the other options are not possible answers.
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No, they are not.