venio

Venio, venire, veni, ventum is a fourth conjugation verb with an unusually tidy perfect: veni is the present stem with a long e and no other change.

That tidiness costs you something. Veni is both "I came" and the imperative "come!", and venit is both "he comes" and "he came", the present and the perfect differing only in the length of the e. Latin readers had the quantity; you have the context. Where a passage seems to shift tense for no reason, this verb is a good suspect.

Its compounds are everywhere and they are not always transparent. Convenio is "to come together" and so "to suit, to be agreed"; invenio is "to come upon" and so "to find"; pervenio is "to arrive"; evenio is "to turn out"; and advenio gives adventus, the arrival, and hence Advent. Off the same family come convention, revenue, income in the shape of proventus, souvenir, and the venue where something takes place. French venir, Spanish venir and Italian venire are the verb itself, still doing the same job.