A conditional clause is a dependent clause that is expressing a condition on which the main clause is dependent. The protasis may be noncommittal (general), more or less probable in the speaker’s mind (more vivid, less vivid), or contrary to fact (unreal).
- “If you are hungry, eat” (I have not expressed an opinion about your hunger).
- “If it does rain tomorrow, we’ll stay home” (it seems more probable to the speaker).
- “If it should clear by noon, we’ll go” (it seems less probable to the speaker).
- “If I were Superman, I could do it” (contrary to fact).
Since the difference is in the mind of the speaker, the terms “more vivid” and “less vivid” are preferred to “more probable” and “less probable.” LaSor, Handbook, 2:207.
Greek:
Greek has first, second, and third class conditions. (GGBB 687)
- A first class condition uses ει in the protasis.
- A second class condition also uses ει but has αν in the apodosis.
- A third class condition uses εαν in the protasis.
A first class condition assumes the truth of the protasis.
A second class condition assumes the protasis to be false.
- Look for ει in the protasis + indicative mood and αν in the apodosis.
A third class condition isn’t sure about the protasis.
- Look for εαν and subjunctive mood in the protasis + any mood in the apodosis.
Hebrew:
The usual conjunction used to begin a conditional clause is אִם. The conjunction כִּי is also used in this way; see Gesenius.