[ a, an, the, Zero Article ]
Roentgen was ___ German physicist who discovered x-rays, revolutionizing medical diagnosis.
a. a
b. an
c. the
d. X [Nothing]

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Correlative conjunctions › View_____ Chelsea _____ Miranda made the basketball team, even though they practiced hard.
A. Either … or
B. Neither … nor
Conjunction › View
I enjoy reading this new magazine. ___, it has good articles.
a. Moreover
b. Nevertheless
c. However
What does “garrulous” mean?
A. Reserved
B. Chatty
C. Reticent
D. Talkative
Tenses › View
I think that they _____ (arrive) tomorrow morning.
A. will arrive
B. arrive