Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in the each of following questions

For eras, musics have performed string violins, which (produce sounds from the vibration of the strings

A. musics

B. which

C. sounds

D. vibration

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.

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.

Hardly he had graduated from Vietnam Naval Academy when he joined Vietnam Coast Guard.

A. he had    

B. graduated from  

C. when       

D. joined

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

Every country has its own traditions, some of them have existed for centuries.

A. Every

B. its own

C. some of them

D. 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.

The world is becoming more (A) industrialized and the number of animal (B) species that have becoming (C) extinct (D) have increased. Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions

A.  industrialized

B. species

C. extinct

D. have

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. 

Genes have several alternative form, or alleles, which are produced by mutations.

A. several alternative

B. form

C. which

D. produced by

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.

Each of the chemical elements have its own standard symbol.

A. of the

B. chemical

C. have

D. its own