There are four oceans in the world.

Further investigation will offer many opportunities to obtain more valuable knowledge of the ocean.

Mountains in the ocean and even whole ranges are still being discovered, and most of them have not yet been explored in detail.

Voyages of exploration were the earliest in the history of studying the ocean.

If we are to judge the future of ocean study by its past, we can surely look forward to many exciting discoveries.

Lobsters belong to a class of marine animals.

Evaporation from oceans, lakes, and rivers creates 90% of the water in air.

The new Mario game is an underwater adventure where he solves the mystery of an ancient kingdom sunk to the bottom of the sea.