puto

Puto, putare, putavi, putatum, first conjugation and fully regular, which after capio and eo is a relief.

The root sense is agricultural: to prune a vine, to clean it up. From tidying branches it moved to tidying accounts - rationem putare is to settle a reckoning - and from reckoning on a tablet to reckoning in the head. That accounting ancestry is why it takes the accusative and infinitive so readily, puto eum venire, "I reckon him to be coming", and why it also takes a double accusative, eum amicum puto. The compounds keep the counting: computo gives count and compute, disputo gives dispute, reputo gives repute, imputo gives impute, and deputo gives deputy. Amputo, "prune away", kept the vineyard sense and then took up surgery.