story: Two boys bought a tub of popcorn at the movie theater. Every time one boy grabbed some, the other would too. They each took turns eating the popcorn. They ended up eating the same amount each. The boys got a refill on popcorn and did it again.
 selected sentence: They each took turns eating the popcorn.
Two boys take turns eating popcorn >Causes/Enables> Two boys eat the same amount of popcorn