Recent studies suggest that we yawn when we get tired as a way to encourage our brains. the theory is that yawning cool the brain, allowing it to work more efficiently. according to webmd's article about these studies, when you yawn, your jaw muscles get stretched, increasing blood flow to your neck, face, and head. also a deep breath during the yawn forces spinal fluid and blood down from the brain. the cool air then cools down these fluids.

which line shows the main idea of the bolded paragraph? we yawn when we get tired as a way to encourage our brains
when you yawn, your jaw muscles get stretched
also a deep breath during the yawn forces spinal fluid and blood down
the cool air then cools down these fluids.

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"the monkey's paw" is a rare story in that the theme is actually stated in the story. sgt. maj. morris tells the whites that the old fakir who put the spell on the paw said, "fate rules people's lives and those who interfere with fate do so to their sorrow." the message is a warning, but mr. white doesn't believe it. even though sgt. maj. morris makes it clear that he tried wishing with unfortunate results and he tries to throw the paw on the fire,   mr. white makes a wish for 200 pounds only to find that he receives the money when herbert dies in a factory accident. according to the fakir, then, because mr. white had wished for something he should not have had, his son lost his life.

the second wish that mrs. white encourages him to make is for herbert's return--one week after his death. when the strange knocking begins at the door during the windy night, mr. white panicks, believing that the previously dead but still mangled herbert could have walked home from the cemetary and is now at the door. because he fears what his wife will find if she opens the door, mr. white makes his third wish--for the noise to stop.

therefore, he uses his three wishes and to his sorrow, loses his son and disappoints his wife, who fervently believed that their son was at the door. she wanted him back, regardless of his condition.

explanation:

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