已知全集U，集合A⊆B⊆U，则有（ ）
A．A∩B=B
B．A∪B=A
C．（∁UA）∩（∁UB）=∁UB
D．（∁UA）∪（∁UB）=∁UB
∵A⊆B⊆U∴A∩B=A，故选项A不正确；
A∪B=B，故选项B不正确；
（∁UA）∩（∁UB）=∁U（A∪B）=∁UB，故选项C正确；
（∁UA）∪（∁UB）=∁U（A∩B）=∁UA，故选项D不正确
故选C
短文填空。（每小题1分，共10分。用方框中的词的正确形式填空，将短文补充完整(注意大小写)。
I’m not 小题1:, I have too many rules in my house, I have to get 小题2: at six o’clock every morning. I can’t meet my 小题3: after school because I have to do 小题4:homework. I can’t watch TV on school nights. And I have to be in bed by ten o’clock. 小题5: weekends, I have to 小题6: my room and wash my clothes. Then I 小题7:to help my mom make 小题8: . Later I have to go to小题9: Children’s Palace to learn piano. I never have any fun. What 小题10: I do ? Zhao Pei |