中国大学MOOC: Since High-speed railway debuted in China with the Beijing-to-Tianjin in 2008, China has built east-west high-speed lines and north-south routes across the country.

An__ of the post’s fundamental role in the creation of the United States requires a little knowledge of the problems faced by the colonies at that time.‍（） A: authorized B: rudimentary C: appreciation D: debuted

11. An ________ of the post’s fundamental role in the creation of the United States requires a little knowledge of the problems faced by the colonies at that time.‍ A: authorized B: rudimentary C: appreciation D: debuted

11. An ________ of the post’s fundamental role in the creation of the United States requires a little knowledge of the problems faced by the colonies at that time.‍‏ A: authorized B: rudimentary C: appreciation D: debuted

Since High-speed railway debuted in China with the Beijing-to-Tianjin in 2008, China has built east-west high-speed lines and north-south routes across the country. A: two, two B: three, three C: four, four D: five, five