The reason why he was late was _______ he had take a wrong bus.
John’s pale face suggested that he ______ill, and his parents suggested that he ______a medical examination.
It is vital that we _____ act out at once to protect the environment.
—Any information about your son?—No. If only I ______ those tough words to him.
---Your sister nearly _______ all her spare time to her study during the three years. ----That's right, or she ________ the first place in her school in the College Entrance Examination.
Zhang Lin was addicted to computer games during his last year in high school , otherwise he ____________a student of Beijing University .