1. B

-> S+tobe/V + different from + N/pronoun 

2. A

-> S +tobe/V + the same +(N) + as + N/pronoun

3. C

-> S+tobe/V + as + adj/adv + as + N/pronoun 

4. B 

->S+tobe/V + different from + N/pronoun  

67. Viet Nam has some kinds of traditional opera such as "Cheo" or" Cai Luong". 

->such as : như là 

68.I don't sing as well as my sister.  

-> S+tobe/V + not + as/so + adj/adv + as +N/pronoun 

69. Ballets and modern dance are not the same. 

-> different : khác = not the same : ko giống nhau 

->  Ba lê và nhảy hiện đại không giống nhau.