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.

Plastic bags are harmful (A) to the (B) environment so (C) they should replace (D) by paper bags.

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.

All the students must hand his essays by the end of the week.
A B C D

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 principle of comprehensive (A) inputs states that the language provided (B) for students should go only a little beyond their current (C) experience and understanding (D).

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.

Their pioneering research (A) showed that the learning motivation of the two groups of learners was quite distinctive (B) from each other, and the comparative (C) group whose learning motivation was stronger performed better than the control (D) group.

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.

Many wild animals are suffering from losing its natural habitats.

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 man bought (A) the old painting and then (B) resold them (C) to a collector at (D) a higher price.

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 manager spends two hours talking with us yesterday.