阿摩線上測驗
38. Some people work better in the morning _____ others are more productive late at night.
(A) once
(B) while
(C) unless
(D) because
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統計： A(3), B(13), C(5), D(5), E(0) #3930936
統計： A(3), B(13), C(5), D(5), E(0) #3930936
