It seems there is a pretty strong correlation between the subjunctive
and the imperitive conditons. For instance Que tenga un buen dia!
means 'have a good day'(loosley), with tenga being a subjunctive form
of tener. Tenga is also the imperitive (sing.formal). I notice this
correlation with many other verbs also.

The imperitive is used to make commands or requests (the only thing
separating these two forms is tone of voice in most cases). The
subjunctive addresses actions as contingencies or hypothetical, not as
fact.

So it seems in a way the concepts are related. If I say 'Take this
note' Tome este aviso. It's a command or request, but also it's
hypothetical since it's not yet known for sure that the note will be
taken. So it seems this would explain why the two forms are often the
same.

So can the imperitive be used across the board instead of the
subjunctive and be reasonably correct most of the time? This is as a
starting position for a beginner, not as an ultimate goal. Also is the
analysis made above reasonable or totally out the window?

Thanks, Patrice

Hello Patrice,

Your hypothesis are interesting but I don't think they are in the
right track. Actually, the coincidences between subjunctive and
imperative modes are quite casual. Let's compare both complete
conjugations:

person - imperative - subjunctive
yo - (it doesn't apply) - tenga
tú - ten - tengas
él/ella/usted - tenga - tenga 
nosotros/nosotras - tengamos - tengamos
vosotros/vosotras - tened - tengáis
ellos/ellas/ustedes - tengan - tengan

(Remember, "usted" and "ustedes" are conjugated like the third person
singular and plural respectively, while having a second person meaning
for a respectful formal treatment.)

The subjunctive has two main uses: to express a desire, a wish: "que
tengas buen dia" (have a nice day), or a possibility: "quizás tengas
un buen día" (maybe you have a nice day).

Instead, the imperative is either an order: "ten limpio tu cuarto"
(keep your room clean); an advice: "ten cuidado" (be careful), or a
request: "ten piedad" (have mercy).

Since orders, advices or requests to a third person (he, she, they)
suggest a second person as an intermediate (otherwise, if speaking
directly to him or her that would become a second person situation, so
we would use the second person form), the order is given in an
indirect form such as "dile a él *que tenga* limpio su cuarto" (tell
him to keep his room clean). Since the verbal form coincides with the
subjunctive mode, and we need the subordinator "que" to introduce a
subordinated proposition, we might mistake it for a subjunctive, but
it still is an imperative because of its intention: a plain order. No
matter how similar it could seem to: "dile a él que tenga un buen día"
(tell him to have a nice day) where the intention is to express a
wish, therefore, subjunctive mode. How can we tell the difference?
Well, turning it to a second person situation: in the first case,
you'd say: "ten limpio tu cuarto", in the second case: "que tengas un
buen día". See how the verbal forms become different: "ten" =/=
"tengas".

I hope this clarifies your comprehension of the differences despite
the similarities between subjunctive and imperative modes.

I'm pleased to have met you again in Google Answers. Thanks for asking.

Best regards,

Guillermo

For now I've confined myself to only thinking of the Usted imperative.
I don't know how I'll ever manage to remember 2 or 3 commad forms. So
yes, the correlation only holds with the sing/formal case. I guess
it's a coincidence.

I think I've ask a question that's over my current level.

Patrice,
I decided to add a comment to this question because I definitely see a
relation between the imperative and the subjunctive.

As to usage, they are two different things. However, the conjugations
are often the same.

The imperative forms of usted, are the same as the subjunctive, as you
already have noted.

Examples:
Venga. Tome. Coma.

The negative imperative forms of tú also take the subjunctive.
No comas. No vayas. etc.

The imperative form of ustedes also use the subjunctive.

The subjunctive is something very complex, and much more than only
irreal or impossible events. I will give two examples to demonstrate
my point:

"No creo que tengas razón."
This is the perception part of the subjunctive, and the fact that "I
don´t belive you´re right" is very true.

"Me gustó que me dieras el coche."
This is the emotion part of the subjunctive, and the giving of the car
also occured (gramatically).

These are only two examples. Fully comprehending the subjunctive will
take you a lot of time, even if you are studying it full time.
However, don´t let this discourage you.

If you would like good explanations of the subjunctive, I suggest you
buy the book "Advanced Spanish Grammar". I think it was written by
Prado. Look it up on Amazon. Another book which explanations of the
subjunctive has helped me a lot is "501 Spanish Verbs". The
explanations are at the beginning of the book. Good luck with your
studying.

Peter

Hello Peter and Patrice,

It's somehow exciting to see natives of another language with such a
thorough understanding of one's tongue that are capable to challenge
one's knowledge on it.

I'm curious about those resources that you mention, Peter. Now, let me
tell you my thoughts on the issue.

If we consider that the imperative mode "borrows" some forms from the
subjunctive, it's obvious that there is a relation between the two
modes. What in my answer I'm warning of is not to infer a semantic
relation, which could lead to misuse, based on the fact of the
morphological relation.

On the other hand, we can also consider that those forms of the
imperative just happen to be identical to the subjunctive ones.

Let's see, for instance, the indicative form "cantamos", which may be
either the simple past (pretérito perfecto simple) or the simple
present (presente) for the first person plural of "cantar". Whether
interpreted as past or present will be defined by the context but, in
any case, we can't infer a semantic relation for the morphological
identity: what means past cannot mean present (unless we were holding
the conversation inside a time machine ;-))

As to other uses of the subjunctive ?which, agreeing with you, is
definitely complex, up to the point that many native Spanish speakers
just replace it by conditional or indicative forms? please note that,
in its more specific use it does not exactly refer to unreal or
impossible events but to events which are not certain, regardless
whether they're possible or not.

Now, your very interesting example "no creo que tengas razón" is
tricky. Actually, the positive, certain part of the phrase lies on
"creo", the fact is that the speaker *doesn't believe* that the other
one isn't right. But whether this one *is* right or not, remains
uncertain, in a very subjunctive manner.

Conversely, in the other example "me gustó que me dieras el coche" the
subjunctive form "dieras" does seem to have lost all of its
subjunctive specificity, taking on a positive sense of a fact actually
occurred in the past.

Patrice's hypothesis on a semantic relation between subjunctive and
imperative, based on morphological coincidences and the uncertainty of
the actual completion of the order or request, is cleaver and
interesting. If I don't stand by it is because the intentions are very
different: The imperative ?be it an order, a request, a suggestion or
a plea- denotes determination to impact on the interlocutor's
behavior, expecting to achieve it. The subjunctive, unless with a
strong use of an imperative or indicative form (such as "impediré que
te vayas" = "I'll prevent you to go"), doesn't imply it by itself
?rather, the speaker assumes no power on the uncertain events
referred. Hope this clarifies the point made in my answer.

Regards,

Guillermo

Sorry, in my last example, I think that I should have translated it:
"I'll prevent you from going (away)".