19. A hot air balloon will rise when its density is ____ of the surrounding air.
(A) the lower density
(B) lower than that
(C) than the lower density
(D) the density is lower than

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統計： A(112), B(1378), C(48), D(27), E(0) #31245

詳解 (共 2 筆)

#214448

背：more than that of + N.
20
1
#466928
hot air balloon 熱氣球
density稠密(度)
surrounding 環境; 周圍的事物
3
0