Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction.
Public health (A) experts say that the money one spends (B) is less than the cost (C) of to treat sickness (D).
A. Public health
B. spends
C. cost
D. to treat sickness
Đáp án : D
Chọn D “to treat sickness” vì sau “of” phải dùng Ving chứ không phải to V. Sửa to treat sickness -> treating sickness.