Big Idea
Por Favor vs. Porfavor is about choosing the word that matches the thought.
Prepositions connect ideas. Do not translate them one by one; ask what relationship they create.
Examples
Example 1
Voy a casa.
I am going home.
Notice a: Direction or destination.
Example 2
Vengo de Colombia.
I come from Colombia.
Notice de: Origin or source.
Example 3
Estoy en clase.
I am in class.
Notice en: Location or setting.
Step 1:Do not ask which English word matches.Step 2:Ask what the speaker means: identity, state, destination, cause, request, or result.Step 3:Choose the Spanish word that carries that meaning.
Watch for this: The trap is translating word for word. Spanish choices usually come from the relationship between ideas, not from a single English gloss.
With Por Favor vs. Porfavor, keep the focus on choosing the word that matches the thought. One clear sentence can teach more than a long rule.