(Situation: A boy has arrived at school. He is walking in the hallway. He is not wearing a school uniform. A teacher says to him, 'You should always wear your uniform to school.')

1. You should always wear your uniform to school.

2. You should always wear your uniform at school.

3. You should always wear your uniform for school.

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Can we use all the prepositions?
What is the difference among them?

All of them work, but #1 is best.

#2 implies that he has other clothing at school in addition to his uniform.

#3 is a bit awkward, but the meaning comes through.

While all three prepositions - "to," "at," and "for" - can be used in this context, there are slight differences in their meanings.

1. "You should always wear your uniform to school."
This sentence emphasizes the action of wearing the uniform as the boy goes towards or arrives at school. The preposition "to" indicates movement or direction towards the destination, in this case, the school.

2. "You should always wear your uniform at school."
This sentence emphasizes the location where the uniform needs to be worn. The preposition "at" indicates the specific place or location, highlighting that the uniform must be worn while the boy is in school.

3. "You should always wear your uniform for school."
This sentence emphasizes the purpose of wearing the uniform, specifically for engaging in school-related activities. The preposition "for" indicates the reason or goal behind wearing the uniform, suggesting that it is necessary to wear the uniform in order to fully participate in school.

In summary, while all three sentences convey the same general message, there are slight nuances in their meanings. "To" emphasizes the action or movement towards school, "at" highlights the location where the uniform should be worn, and "for" emphasizes the purpose or goal of wearing the uniform in relation to school activities.