Ammonia______as the refrigerant in the first practical refrigerator, made by Kar

游客2024-01-02 53

问题 Ammonia______as the refrigerant in the first practical refrigerator, made by Karl von Linde in 1876.

选项 A、used
B、had used
C、is used
D、was used

答案 D

解析 The sentence needs a passive-voice verb; was used agrees in tense with the other verb in the sentence, made, and the time marker 1876.

转载请注明原文地址:https://tihaiku.com/zcyy/3328022.html

相关试题推荐

随机试题

最新回复(0)

Somepeoplearepracticalanddown-to-earth,while______aredreamers.A、anotherB