Câu hỏi: Choose the correct answer to fill in the blank. 

A. that are

B. being

C. are

D. are being

Câu 1: In 1850 ........................ established one of the first detective agencies in theUnited States.

A. it was detectivePinkerton

B. detective Pinkerton 

C. detective Pinkerton who

D. when detectivePinkerton

Câu 2: John always .................... his car in the lot by the school.

A. park

B. parks

C. is parked

D. was parked

Câu 3: In 1849, Walter Hunt, ...................... American inventor, patented a designthat served as the basis for modem safety pins.

A. an

B. he was an

C. who

D. was an

Câu 4: Ansel Adams was a landscape photographer ............................. photographs show the nature of the western United States.

A. of his

B. whose 

C. of whom

D. his

Câu 5: Computers are considered as .................... tools today.

A. the most modern

B. more modern

C. modern as

D. much modern than  

Câu 6: Commercial centers are ................ they were many years ago.

A. as popular than

B. the most popular

C. the most popular than

D. more popular than