Landscape

A beach is the sandy edge of the sea or a lake. A beach is sometimes called the shore. People like to go down to the beach and sit in the sun, make sandcastles or go swimming.

A bog is an area where the soil is very wet and is mostly made up of rotting plant matter.
A bog is similar to a moor or swamp.

Brine is salty water. You can use brine to preserve things like olives. People describe the sea as brine.
Salty water used for medical purposes is called saline.

A canal is a watercourse that has been made by people rather than a natural watercourse. Canals are generally cut to make a transportation path, for boats to travel along.

A cave is a hole in the side of a hill or mountain that is big enough for people or animals to get inside. Many animals, like bears and bats live in caves.
Limestone caves are often full of stalactites and stalagmites.

A chasm is an extremely deep hole or fissure in the ground. Chasms are usually very large, big enough for a person to fall into.

The coast is where land meets the sea.
Some other words you can use instead of coast are shore and beach.

A crater is a large, circular hole in the ground that could have been caused by several different things. Craters can be many kilometers wide and very deep.
Craters are found on top of volcanoes, and they can be caused by meteors hitting the Earth. They are sometimes caused when the ground collapses above a large underground chamber like an old mine or a cave.

A dam is a large wall built across a river to change the natural flow of water and make a deep lake form behind the wall. The water from dams is often used to water farm or supply water to a city, or to make electricity.

extension A drain is a type of hole, usually attached to a drainpipe, where water can escape from somewhere like a bath, washbasin or road. The entrance to a drain is usually covered by a grate.
You can use the word drain to describe the process of the water leaving somewhere, or the hole through which the water escapes.