509. The first _____ appeared during the last period of the dinosaurs’ reign.
a. flowers are plants
b. plants have flowers
c. plants flowers
d. flowering plants
510. The earliest medicines _____ from plants of various sorts.
b. they obtained
c. were obtained
d. they were obtained
511. Simple sails were made from canvas _____ over a frame.
a. a stretch
c. was stretched
d. it was stretched
512. Pluto’s moon Charon _____ in a slightly elliptical path around the planet.
b. is moving
c. it was moving
d. in its movement
513. Techniques of breath control form an essential part of any _____ program to improve the voice.
a. it trains
514. Robert E. Lee _____ the Confederate Army to General Grant in 1865 at the Appomattox Courthouse.
b. he surrendered
515. The pituitary gland, _____ the brain, releases hormones to control other glands.
a. found below
b. it is found below
c. its foundation below
d. finds itself below
516. At around two years of age, many children regularly produce sentences _____ three or four words.
a. are containing
517. Multinational companies _____ it increasingly important to employ internationally acceptable brand names.
b. are finding
c. they find
d. they are finding
518. The cornea is located under the conjunctiva, on _____ of the eye.
a. the part is exposed
b. exposed the part
c. the exposed part
d. exposes the part
519. By the 1920s, many radio transmitters had been build.
ubah build jadi built
520. Fish farming has rose in the United States in recent years.
ubah rose jadi risen
521. Cro-Magnon man was names after the caves in southwest France where the first remains were discovered.
ubah names jadi named
522. Lassie, the famous collie who made her first screen appearance in 1943, has always be played by a male dog.
ubah be jadi been
523. President George Washington was inaugurates on the steps of the Federal Building in New York City.
ubah inaugurates jadi inaugurated
524. By 1627, Plymouth had became a viable and growing community of fifty families, twenty-two goats, fifteen cows, and more than fifty pigs.
ubah became jadi become
525. Tobacco was the crop on which the eminence of Williamsburg and the prosperity of Virginia were base.
ubah base jadi based