zhè / piàn / hǎi / yù / shuǐ / shēn / bù / kě / cè / pǔ / tōng / yú / chuán / bù / néng / kào / jìn

这片海域水深不可测，普通渔船不能靠近。

The waters in this area are unfathomably deep, so ordinary fishing boats cannot approach.