were learning about affirmative/negative usted/tu commands and on the model it says "Tenemos pelo sucio. (el perfume)" and then the answer is "no lo compren" why compren, why not compre?
Look at the endings.... Is one singular and one plural? Is tenemos singular or plural?
It will be that easy = singular or plural.
If you are speaking to one person, saying don't buy: no compres (tú) and no compre (usted)
If you are speaking to more than one person = no compréis (vosotros) but no compren ustedes)
That's it for the negative, HOWEVER the affirmative command for tú is just like the 3rd-person singular of the Present tense.
Compra (tú) but Compre (usted)
Comprad (vosotros) but Compren (ustedes)
Sra
When using affirmative or negative commands in Spanish, the form of the verb changes depending on who you are addressing and whether the command is affirmative or negative.
In the given example, "Tenemos pelo sucio" means "We have dirty hair." The command that follows is meant to offer a solution to this problem. To translate the command "Don't buy it" in Spanish, you need to understand that it's referring to "the perfume" mentioned in parentheses.
The verb "buy" in Spanish is "comprar." To form the negative command for "you all" (ustedes), the regular -ar verb ending "-ar" is replaced with "-en." Since "ustedes" is the subject of the command, we would use "comprueben" for the affirmative command.
In this case, the negative command "Don't buy it" translates to "No lo compren" in Spanish. "No" indicates the negation, "lo" refers to "the perfume" (a direct object pronoun), and "compren" is the command form of the verb "comprar" for "ustedes" (you all).
So, "compren" is used because it's the correct command form of "comprar" for addressing "ustedes" in the negative command, asking them not to buy the perfume.