There are two conditional particles, εἰ and ἐάν, usually translated if, which introduce a condition which must be met for a consequence or conclusion to follow.
|ἐάν θέλῃς, δύνασαί με καθαρίσαι|
|ean thelēs, dynasai me katharisai|
|if you are willing, you are able me to make clean|
|if you are willing, you can make me clean.|