I've just recently stumbled across the very existence of the Subjunctive tense a few days ago. Just yesterday I was talking to my Guatemalan friend asking her if she could explain it a little better for me, and she said she didn't even know what it was. I explained it first as "when you say 'quieras' or 'puedas' instead of 'quieres' or 'puedes'." She still didn't understand, so I tried to give examples such as "si quieras caminar, podemos" or "espero que puedas caminar" and she still said that was wrong. I am sorta confused now because I thought the subjunctive was used to express doubt or emotion, and I was seeking her help to better explain it to me and, primarily, to give me examples. I did not expect her to not know it, especially sense I've read that it's very commonly used. I know my examples were probably completely wrong (and please tell me if they were), but I thought she would at least be able to correct me. My question is: is this just a part of Spanish that is "proper" and not used in daily life? Is it a regional thing- some countries use it and others don't? Or were my examples just too misleading? (I should also note, she came here (the United States) in 8th grade and has only been here for a year. She has come to speak English very well, and I don't know about her education in Guatemala or lack thereof.)
First of all, note the subjunctive is a mood (or modo in Spanish), not a tense (or tiempo in Spanish). Spanish verbs can be conjugated considering the mood and the tense. There are three moods: indicative, imperative and subjunctive, all of which comprise different tenses. The conditional was considered a mood as well some decades ago, but now it’s considered a tense within the indicative mood. For further clarification see this conjugation table.
Is this just a part of Spanish that is "proper" and not used in daily life?
Absolutely not. The subjunctive mood is key in Spanish and it works both on a grammatical and a semantic level. Sometimes its use is necessary just because a given verb requires it (grammatical level), and sometimes its use will change the meaning of the sentence (semantic level).
An example of the grammatical level would be: la lluvia hizo que el parque se inundarasub and la lluvia inundóind el parque. Both sentences mean pretty much the same thing, but the first requires a subjunctive tense because hacer is a "verb of influence" and such verbs are generally followed by a subjunctive. However, this subjunctive doesn't indicate any doubt or emotion (the park was flooded, there's no uncertainty whatsoever), so it's semantically superflous, but mandatory for the sentence to be grammatical.
An example of the semantic level would be adjectival clauses, already adressed in this question or this one (both in Spanish). Consider the sentences: Quiero un vestido que esind rojo and Quiero un vestido que seasub rojo. In the fields of grammar, both are equally correct; but in the fields of semantics, there's a difference in meaning, the former indicating the dress is a specific one and the latter indicating it's an indefinite one, which is related to the next question.
Is it a regional thing- some countries use it and others don't?
I highly doubt there's any Spanish speaking country with no subjunctive at all. As explained above, the subjunctive mood may change the meaning of a sentence, so its exclusion would impoverish the language. Now, it is also a possibility that its usage varies from one country to another (and I wouldn't be surprised if that were the case). However, I'm sceptical about the idea that there's any country in the world where "espero que puedes caminar" is acceptable. Maybe in Guatemala it is; after all, I've never been there. It sounds fishy, though. Either way, if there's any country where the subjunctive mood doesn't exist, such dialect would be deemed as incorrect by any Spanish speaker that doesn't know it exists (disclaimer: no dialect is "incorrect", but some could be so non-standard that whoever is not familiar with it or has never heard about it would consider it wrong, so it isn't advisable for learners).
Were my examples just too misleading?
The first one actually was a little misleading. In "si quieras caminar, podemos", you are dealing with conditionals. As you probably know, there are four types of conditional sentences in English (type 0, type 1, type 2 and type 3), as well as mixed conditionals. Conditionals in Spanish should be fairly easy to understand because they work almost exactly the same way they do in English. In "if you want to go for a walk, we can", you have no subjunctives, so you don't need them in Spanish either. The correct sentence would be: "si quieres caminar, podemos". Your second sentence was fine because "espero que" expresses a wish.
I don't know what to tell you about your friend. Maybe it's a dialectical thing, maybe you were pronouncing it in a way she didn't understand you, or maybe it's something else. The subjuntive mood is certainly used in daily life, even among groups with no formal education, although not everybody is aware of it or consciously knows about moods or how the rules that govern them work. In my opinion, when learning the most technical aspects of a language, few people besides teachers are more useful than a good text book.
Some interesting readings on the subjunctive mood (only in Spanish):
- Aproximación al subjuntivo en las subordinadas adjetivas explicativas, by Vásquez González.
- Los modos verbales del español actual, by Vásquez González.