Complex sentence: Today, both narrow-body and wide-body trijet production has ceased for commercial aircraft, being replaced by twinjets which are quieter and more efficient, and with ETOPS restrictions eased, became more suitable for long-haul overwater operation.
Split into simpler sentences: Today, both narrow-body and wide-body trijet production has ceased for commercial aircraft, being replaced by twinjets which are quieter and more efficient. With ETOPS restrictions eased, twijets became more suitable for long-haul overwater operation.