21. In 1990, _____ Belgian inventor by _____ name of Bakelite invented the first of the modern plastics.
A. a; a B. a; the C. the; a D. the ; /
22. There _____ two experts doctors _____ the wounded soldier.
A. is said to be; attending to B. are said to be ; attending on
C. saying to; attend to D. to say to have ; to attend on
