one part of a whole

to stop for a short time

to hold or include something

to rise to the top

to move between habitats or places

a rule or piece of advice about how to behave

to organize or arrange

Babies make only _____ cooing and babbling sounds

before they say more complex words.

The two _____ of smog are smoke and fog.

When I was studying for the test,

I _____ because my eyes were getting tired.

The science book _____ a chapter on pollution.

The submarine had been underwater for two weeks

and needed to _____ for supplies.

Some hummingbirds _____ 500 miles across the Gulf of Mexico.

Our school has a student handbook that lists the _____ for behavior.

To get students to school on time,

bus drivers _____ the order in which they pick them up.