Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
It was in 1971 that transatlantic supersonic transportation became commercially availability.
A.that
B.supersonic
C.became
D.availability

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
It is important that you turned off the heater every morning before you leave for class.
A.before
B.turned off
C.It
D.leave for

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
Physics and mental exercise has been found to be beneficial for our brains, but scientists have now found it could also improve the learning ability of our children.
A.Physics
B.has been
C.it
D.learning ability

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
The bitcoin system created in 2009 by an enigmatie person named Satoshi Nakamoto.
A.The
B.created
C.enigmatie
D.named

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
A large number of entries has updated in the latest edition of the encyclopedia recently.
A.large
B.has updated
C.of
D.recently

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
Some snakes have holow teeth are called fangs that they use to poison their victims.
A.Some
B.are called
C.use
D.their

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
There are different hundreds of species of butterflies in Cuc Phuong National Park.
A.There are
B.different hundreds of
C.species of
D.in

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It is imperative that these materials send to the director immediately.
A.is
B.send
C.the
D.immediately

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
On the floor of the Pacific Ocean is hundreds of flat-tipped mountains more than a mile beneath sea level.
A.more than
B.On
C.beneath sea level
D.is hundreds of

Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.
The federal government recommends that all expectant women will not only refrain from smoking but also avoid places where other people smoke.
A.recommends that
B.expectant
C.will not only refrain
D.smoke