Ancient Greek conditional clauses

Conditional clauses in Ancient Greek are clauses which start with εἰ (ei) "if" or ἐάν (eān) "if (it may be)". ἐάν (eān) can be contracted to ἤν (ḗn) or ἄν (ā́n), with a long vowel. The "if"-clause of a conditional sentence is called the protasis, and the consequent or main clause is called the apodosis.

The negative particle in a conditional clause is usually μή (mḗ), making the conjunctions εἰ μή (ei mḗ) or ἐὰν μή (eàn mḗ) "unless", "if not". However, some conditions have οὐ (ou). The apodosis usually has οὐ (ou).

A conditional clause preceded by εἴθε (eíthe) or εἰ γάρ (ei gár) "if only" is also occasionally used in Greek for making a wish. The conjunction εἰ (ei) "if" also frequently introduces an indirect question.