The present participle in the Greek indicates an incomplete action with no indication of future completion. “Perish,” although some see it as indicating imminent completion, is proper since it indicates the act as incomplete (whereas “perished” would indicate completion). The typical present participle for a transformative verb (e.g. “are perishing”) can be understood as the present progressive, which not only indicates progression but also imminent completion. Thus, the semantic effect of either construction is the same to the English mind.
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