What Is A Reflective Statement?

A reflective statement shows that you have thought about something yourself. If you just repeat what someone else has told you that is not reflective.
If some thing happens and you consider why it happened and whether it would have been the same if certain factors had been different , you would be thinking reflectively. If you then write about what you have considered you would be making reflective statements.
For example a teacher might reflect on why a student misbehaves in their class. They might consider whether the work is too hard or too easy for that student, or whether they need to change their own behaviour, being stricter or being more friendly, or they might think that they need a more snappy start to lessons or a more interesting topic to involve this student, they might decide to get to know the student better or they might consider excluding the offender. All that thinking would be reflecting on a problem. Telling someone about these thought would be making reflective statements.
To get started you could reflect on in what ways 2 things are the same or different.

My student may behave in that manner as the work may be too hard.