¡¡¡¡1. Quasars __________ emitting extremely intense radio waves and visible radiation.

¡¡¡¡(A) Star-like objects are

¡¡¡¡(B) Star-like, they are objects

¡¡¡¡(C) are star-like objects

¡¡¡¡(D) are they star-like objects

¡¡¡¡2. Mary Cassatt specialized __________ mothers with their children.

¡¡¡¡(A) painted

¡¡¡¡(B) who painted

¡¡¡¡(C) paintings

¡¡¡¡(D) in painting

¡¡¡¡3. Gorillas are quiet animals, __________ they are able to make about twenty different sounds.

¡¡¡¡(A) how

¡¡¡¡(B) in spite of

¡¡¡¡(C) because of

¡¡¡¡(D) even though

¡¡¡¡4. From 1946 to 1949, __________ William Henry Hastie served as governor of the Virgin Islands.

¡¡¡¡(A) the lawyer

¡¡¡¡(B) he was the lawyer

¡¡¡¡(C) the lawyer who

¡¡¡¡(D) was the lawyer

¡¡¡¡5. __________ struck, a tuning fork produces an almost pure tone, retaining its pitch over a long period of time.

¡¡¡¡(A) When is it

¡¡¡¡(B) One is

¡¡¡¡(C) When it is

¡¡¡¡(D) Is one

¡¡¡¡…¢¿¼´ð°¸£º

¡¡¡¡CBDAA