All the guests at the party were dancing and singing happily _____ the electricity was cut off.

下列各句中划线词与现代汉语意思相同的一句是

________ by the heavy snowfalls, Chenzhou, a city in South China, was cut off from the outside,________ water and electricity shortage.[ ]

Has Tom finished his job yet? —I have no idea of it; he _____ it this morning

(2013·高考北京卷)I have an appointment________DrSmith，but I need to change it