Choose the phrase that best completes the following sentence. The principle of ______ states that, in proper sentence structure, singular subjects must take singular verbs and plural subjects must take plural verbs.

Even though the stinging cold isn't exactly what I would wish for in a climate, I intend to spend a good three years of my life at the North Pole.

Their bird, an affectionate but mischievous white cockatoo, routinely toured the neighborhood on a skateboard.

For more than eight years, Waldo has been trying to worm his way into our secret society.

Mr. Dillon met with his new employees and tried to instill in them the drive to succeed that had characterized his sales teams in the past.

My husband was worried that the kids were staying up too late every night.

Even though the stinging cold isn't exactly what I would wish for in a climate, I intend to spend a good three years of my life at the North Pole.

The principle of ... states that, in proper sentence structure, singular subjects must take singular verbs and plural subjects must take plural verbs.

Because of the abundant use of insecticides and pesticides in the world today, my embarrassing dandruff problem has improved considerably.

Dazed and disheveled, her brow furrowed with anxiety, Helen emerged from the mountain cave.

Sitting in a tree at the top of the garden was a huge bluebird with long, yellow tail feathers.