You can only swim in water, not in sand. No animal can swim in sand.
A penguin is not a land animal. This animal can swim and dive in water. they catch their food in water too.
This animal is not adaptted to salt water.
Animals swim because they have these special structure, and this are the fins and tails, but they cannot swim if they cannot breath under water and this is called gills. It really depends on the type of animal you are talking about. If you are takling about a shark or fish. Then, see above. If you are talking about an animal such as a hippopotums then they simply do what we humans call a 'Doggie paddle' they use their legs to basically 'Walk' through the water.
Fish
this animal is a duck with a adaption to help live and swim in the water .,,,,.
The sperm cells of the plant can swim. They swim to the egg cells to reproduce.
Penguins
Yes. Animal Plankton (very tiny orgaisms that swim through the water and is basically food for the puffer fish.)
You simply use the normal movement keys and mouse look to swim through the water freely, you automatically swim when you enter water.
a lizard is a green creature that can camouflage, can swim in the water and bumpy
A flagellum is actually a sort of 'tail' that the single-celled animal whips back and forth to "swim" through liquid, like water.