单项选择题
Because Edgar was convinced of the accuracy of this fact, he（）his opinion.
A. struck at B. strove for C. stuck to D. stood for
单项选择题 Don't rest on your laurels;（）your success and start looking for new markets now.
单项选择题 Our visual perception depends on the reception of energy reflecting or radiating from（）which we wish to perceive.
单项选择题 He（）that he has discovered a new planet.
