单项选择题
A.rough B.rude C.polite D.troublesome
It was well known that Thomas Edison（）the electric lamp...
单项选择题It was well known that Thomas Edison（）the electric lamp.
A.invented B.discovered C.found D.developed
It was in（）the American astronauts succeeded in landing...
单项选择题It was in（）the American astronauts succeeded in landing on the moon.
A.when B.the moment C.which D.that
It was a great pleasure（）me to be invited to the party....
单项选择题It was a great pleasure（）me to be invited to the party.
A.for B.on C.to D.of
