This passage is mainly about_____
A.antibiotics in the field of medicine
B.the validity of folk remedies and their use for advances in modern medicine
C.using folk medicines in place of modern medicines
D.isolating antibiotics in cheese, sugar, and slime

_______(50)
A.last
B.stand
C.remain
D.go

_________(48)
A.natural
B.real
C.living
D.genuine

________(46)
A.result
B.product
C.development
D.reaction

________(44)
A.sooner
B.rather
C.either
D.neither

_________(43)
A.lone
B.individual
C.lonely
D.alone

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions.
It is becoming extremely difficult to grow enough to feed the world’s rapidly increased population.
A.It
B.extremely difficult
C.to feed
D.increased

_______(41)
A.Still
B.Despite
C.Yet
D.Although

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions.
It is believed that in the near future robots will be used to doing things such as cooking.
A.it
B.the near future
C.used to doing
D.such as

Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction in each of the following questions.
The more frequent you exercise, the greater physical endurance you will have.
A.frequent
B.exercise
C.greater
D.will have