1.   More than a dozen of those vessels already are plying the oceans.

2.   They captured the last of the great liners and tall ships that once plied the oceans, and the exhibition includes a selection of these prints.

3.   Even when modernization is finished, the canal will not be able to accommodate some of the mammoth supertankers now plying the oceans.

4.   The highly-decorated Cousteau had used the Calypso to ply the oceans in a career dedicated to marine conservation.