Tense
Tense is when an action happens (past, present, or future) as opposed to aspect, which is how it unfolds.
English usually bundles the two together ("was eating" = past + ongoing). OVP sometimes keeps them more separate: it marks the future with -wei (tüka-wei, "will eat"), but leaves past-vs-present to context. The ongoing suffix -ti can be "is eating" or "was eating."