单选题 I have heard both teachers and students ______ well of him.
  • A. to speak
  • B. spoken
  • C. to have spoken
  • D. speak
【正确答案】 D
【答案解析】[解析] 不定式在感官动词后面作宾补时，to应省略，如：feel，hear，listen to，look at，notice，observe，see，watch等都属感官动词。