[ Modals for Obligation ]
You _____________________ pay attention in class.
A. must
B. mustn’t

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Vocabulary › ViewTaking responsibility for one’s own actions
A. Accountability
B. Conscience
C. Temperance
D. Beneficence
Grammar › View
Yuri Gagarin was one of the pioneers of space _____.
A. exploration
B. explorer
C. exploring
D. explorers