τὸ πλῆθος οὐκ εὐαρίθμητον ἦν → the crowd wasn't easy to count, the crowd was not small, it was not a small crowd
excuse: P. and V. πρόφασις, ἡ.
pardon: P. and V. συγγνώμη, ἡ.
admit of extenuation: P. and V. συγγνώμην ἔχειν.