the dolphin is often called a fish. it is really a mammal that lives in the sea. the dolphin must come to the surface to breathe. it can stay underwater six minutes before returning for air. often refferred to as the ''prankster of the sea,'' the dolphin is a fiendly animal. it seems to enjoy its contacts with humans.

Question

the dolphin reaches a length of 8 to 12 feet. it swims incredibly fast at speeds up to thirty miles per hour. the animal makes a large number of sounds. these sounds help the dolphin get about. the sound waves tell the dolphin what obstacles are in its path.
dolphins travel in schools. highly social, the animals help each other. many scientists believe the dolphin is a highly intelligent animal. some think it is smarter than the ape.

the questions is that i need to underline the plural word so are those the right word that i need to underline or do i need to add more.
WORDS ( minutes, contacts, humans, feet, sounds, sounds, waves, obstacles, dolphins, schools, scientists) need answer thanks soo much :)

Answer 1

First of all, what about capitalization of the first word of a sentence?

I believe you missed "speeds" and "animals."

Sra

Answer 2

They are all right -- but you missed

speeds, miles, animals