Questions about the Imperative
Q: Why is it Firma la carta and NOT Firmas la carta ?
It is true that the indicative tú form of verbs ends in -s. The one exception though is the affirmative imperative structure. Here, the tú form takes the 3rd person singular present indicative ending. The negative tú form follows the 2nd person subjunctive form, e.g.: No firmes la carta.
Q: Why is it ¡Dámelo! and NOT ¡Dálome!?
Remember the order of pronouns is ALWAYS indirect object first ("to/for whom"), then the direct one ("what").
Q: Why is it ten tu comida and NOT tiene tu comida?
The verb tener has an irregular affirmative tú command and does not follow the 3rd person singular present form used for regular tú commands.
Q: Why is it dígamelo and not me lo diga?
Remember that the pronouns are attached to the end of affirmative commands, requiring an accent. The pronouns only occur before the verb for negative commands, e.g.: No me lo diga.
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