clarification

Question

I believe that a couple of the examples used are commands (Imperatives), not subjunctive. Please clarify. Thanks

example:

¿Dígame? - Hola, ¿puedo hablar con Juan?[on the phone, lit: speak to me] Hello? - Hello, may I speak to Juan?

Accepted Answer

Hola Carl
I wouldn't say the fact that we use the subjunctive when we use a command for the formal "usted" is because we want to add politeness to the command. There is no other way to express a command if you are talking to someone formally.
However, if there is no mention of the pronoun usted in that command and you can only see the verb, seeing it in the present subjunctive form will indicate that it is a command directed to a person "formally":
Firme aquí. = Firme usted aquí.
Salgan por esa puerta. = Salgan ustedes por esa puerta.
These verbs conjugated in the present subjunctive will indicate the formallity of that command, as opposed to:
Firma aquí. (imperative for tú)
Salid por esa puerta. (imperative for vosotros)
Saludos

Answer

Hola Papi
Yes, you're absolutely right about the subjunctive and its different tenses. 
I think the confusion comes when some people use the word "command" to refer to the imperative. A "command" is simply "giving an order", and we give commands in different ways in Spanish. One way is by using the "forms" of the imperative. The imperative can be an affirmative one or a negative one, i.e. you can say to someone "do something" or "don't do something". When we say to someone: do something! we use what we call the imperative affirmative forms, that works in different ways depending to who the order it directed to. 
Here you can find the lessons for that:
Imperative (affirmative) for most verbs (tú)

¡Come tu comida!
¡Limpia tu habitación!

Irregular imperative (affirmative) (tú)

¡Ven aquí!
¡Pon eso allí!

Imperative (affirmative) (vosotros)

¡Venid aquí!
¡Hablad más alto!

So far, all these above are not using at all the present subjunctive forms of the verbs. However if the commands are negative (don't do something!) you then make that command by using the present subjunctive conjugation of the verb, and this is for all possible subjects (tú, vosotros, nosotros, used, ustedes)

¡No comas! (tú)
¡No comáis! (vosotros)
¡No comamos! (nosotros)
¡No coma! (usted)
¡No coman! (ustedes)

Now, what happens with the affirmative commands for usted, ustedes, and nosotros? We also use the present subjunctive forms for these:

¡Coma usted!
¡Coman ustedes!
¡Comamos!

Have a look at these other lessons:
Forming the imperative for usted/ustedes/nosotros/nosotras (affirmative and negative commands)
Forming the Spanish imperative of tú/ vosotros/vosotras (negative commands)
I hope this clarified it a bit more. I've noted down though to give some space in Kwiziq Spanish for extra clarification on "commands" and "imperative".
Saludos 
Inma

Answer

Hola Papi
The example that you mention with "Dígame" is using the present subjunctive form "diga". It is a direct command but when we use the "usted" form, which is the case of "diga" we need to conjugate the verb in the present subjunctive. 
If we gave a command informally using the tú form, then you´d need the Imperative form. See the difference here:
Talking to a friend:
"Dime lo que Laura te dijo ayer" (Tell me what Laura told you yesterday)
Talking to a client:
"Dígame su dirección y le enviaré los documentos" (Tell me your address and I will send you the documents.)
The second is used formally. In this case, the form used is the present subjunctive.(diga)
You will find all the information here. Have a look.
Hope it helps
Saludos
Inma

Answer

Ok. I get it.  Without arguing semantics, I think it
might be a benefit to the students, like me, to say these particular forms are
formed or conjugated the same, but that the examples are commands, not
subjunctive.  The title of the grammar being discussed is "Conjugate
yo-go verbs in El Presente de Subjuntivo" making me believe we are
learning about the subjunctive, and the examples would be subjunctives, not
imperatives, which work very differently.  You would not add pronouns to
the ends of the present subjunctive, but rather commands. Honestly, I am just
trying to be helpful. Thank you for all you do!

Answer

Hola Inma,Re: "examples used are commands (Imperatives), not subjunctive."discussionWould it be correct to assume that using the Subjunctive in the case of "usted" is a form of politeness?  If that is correct, I will scream "alleluia"!Nicole

Answer

I may be missing it but did someone answer Nicole's question about subjunctive being used as a form of politeness in Usted commands? Generally I find this whole area of grammatical politeness, commands included but more broadly, really mysterious.

Answer

I may be missing it but did someone answer Nicole's question about subjunctive being used as a form of politeness in Usted commands? Generally I find this whole area of grammatical politeness, commands included but more broadly, really mysterious.

Answer

Inma,From my understanding of verb trees and their conjugations, the subjunctive is conjugated and acts like other verbs.  Things like placement of pronouns go before conjugated verbs, attach to infinitives, and may be attached to present participles.  Whereas commands (not thought of as normal verb conjugations) attach pronouns for affirmative and are placed beforehand for negatives.For these reasons, I think of "Dígame" as a Command.  However, according to your explanation, something about my understanding of "verbs" and "Commands" is not correct.

Answer

Sometimes the nuances are tough to catch. Attachment of pronouns would normally not be done if it was from the subjunctive. However, it seems a level of politeness or wish seems to drive this nuance. I did find this explanation:

Proclisis (objects before the verb) is the norm in modern Spanish except for verbs in the imperative and exhortative subjunctive which most of the time functions as a pseudo-imperative. (https://spanish.stackexchange.com/questions/10710/object-pronouns-with-the-subjunctive).