According to the passage, a heat pump is _____.
A:only used at night
B:only used in summer
C:only used in winter
D:used in summer and in winter as well
答案: used in summer and in winter as well
相关试题
A:only used at night
B:only used in summer
C:only used in winter
D:used in summer and in winter as well
答案: used in summer and in winter as well