We/ had better/ cycle/ school/ every day/ keep fit/ save / environment.
A. We had better cycling to school every day to keep fit and save the environment.
B. We had better cycle to school every day to keep fit and save the environment.
C. We had better to cycle to school every day keeping fit and save the environment.
D. We had better cycles to school every day to keep fit and saving the environment.
Chọn B, sau had better + động từ nguyên thể không to em nhé