[ Grammar ]
The first laser ——- in 1960 by Maiman almost half a century after the publication of Einstein’s theory of radiation which ——- the possibility of laser operation.
A. has been demonstrated / had shown
B. had been demonstrated / showed
C. was demonstrated / showed
D. demonstrates / was shown
E. was being demonstrated / shows
Select your answer:
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Grammar › ViewWhen my uncle saw that beautiful lady across the street, he could not take his eyes ____ her.
A. at
B. off
C. on
D. away
Grammar › View
She ______ the piano.
A. can play
B. can to play
C. cans play