waves / high tide / low tide / undertow
The photo shows a wave. When the wave falls, we say it breaks.
Sometimes you can feel a “pull” as the water goes back into the ocean after the wave breaks on the beach. This “pull” back towards the ocean is called an undertow. Be careful, because it can be strong!
The general level of the ocean water rises and falls too. High tide is when the water level is high and it comes up far onto the beach, and low tide is when the water level is low.
lifeguards

Lifeguards help swimmers stay safe.
Lifeguards are professionals who work at the beach (or at swimming pools) to help swimmers stay safe. If someone is in danger, the lifeguards can rescue them from the water and give emergency medical help.
seaweed
Sometimes, you see plants from the ocean wash up onto the beach. These plants are called seaweed. In some cultures (like Japanese), seaweed is eaten for food.
shells (seashells)

Do you like to collect seashells on the beach?
If you’re lucky, you might find some colorful seashells (or shells) on the beach!
boat / ship
In general, the word boat is used for smaller vessels. Boats can be powered by a motor (motorboat or speedboat), by the wind (sailboat), or by manpower (rowboat).
The word ship is used for larger vessels, like the cruise ship in the picture. There are also cargo ships (used to carry products from one country to another) and warships (used for combat).
The type of vessel that travels under the water is called a submarine.
whale

Whales are very large ocean animals.
shark

Watch out for sharks!
jellyfish

Some jellyfish can also be dangerous.
stingray

Stingray is another common fish.
seagull

You often see seagulls near the ocean.
scuba diving
You need special training and a license to go scuba diving. This scuba diver is wearing flippers on his feet, an oxygen tank on his back, and a mask on his face.
snorkeling

Snorkeling is done on the surface.
Snorkeling is different from scuba diving because it is done only on the surface of the water; you don’t go down deep. This snorkeler is looking at a coral reef.
swimsuit / one-piece / bikini

Two styles of swimsuit for women.
Swimsuit or bathing suit is the general term for what you wear to go swimming, for both women and men.
Styles of women’s swimsuits include one-piece swimsuits and bikinis.
briefs (speedo) / trunks

Different styles of men’s swimsuits
Men’s swimsuits include briefs (also called a speedo), which is often worn by athletes and professional swimmers. Another common style is trunks or swim trunks, which look like long shorts.
sandals / flip-flops

Flip-flops are a specific type of sandal
Sandals are the general word for “open” shoes. Flip-flops are a specific type of sandal. They are often made of rubber and are designed like in the picture above. The name “flip-flop” comes from the sound they make when you are walking!
sunscreen / sunblock

You should always use sunscreen!
Sunscreen or sunblock is the lotion you apply to your skin to protect it from the sun.
tan / sunburn

Don’t get sunburned – ouch!