subjunctive case and si

Question

does one always use the subjunctive case when using "si" as an if clause?

Answer 1

No

Here is a link to a very nice discussion: link text

From that:

Sentences in which the condition is likely or reasonably likely. This is known grammatically as an open condition. For example, in the clause si llueve ("if it rains"), rain is seen as a distinct possibility.

Sentences in which the condition is contrary to fact or is unlikely. For example, the clause si lloviera can be translated as "if it were to rain." Note the difference in meaning from the example above; in this case, while rain is a possibility, it is seen as unlikely. An example of a contrary-to-fact condition is a clause such as si yo fuera rico, "if I were rich." Grammatically, contrary-to-fact and unlikely conditions are treated the same way.

The correct verb tense following si can be observed in the above examples. In open conditions, conditions where the possibility is reasonably likely, si is followed by the present indicative tense (the most common tense, probably the first one you learned as a Spanish student). If the condition is unlikely or false, a past subjunctive (usually the imperfect subjunctive) is used. This is the case even when the condition is something that refers to the present.

Answer 2

And remember never follow si by the present tense in the subjunctive mood!

Answer 3

No,

Si aprendo español, seré bilingüe. If I learn Spanish, I'll be bilingual.

Si me voy ahorita, llegaré temprano. If I leave right now, I'll arrive early.

Si ella come su almuerzo, no tendrá hambre más tarde. If she eats her lunch, she won't be hungry later.