C:某无色气体能使湿润的红色石蕊试纸变蓝,该气体的水溶液一定显碱性
A:加入BaCl2溶液有白色沉淀产生,再加盐酸,沉淀不消失,原溶液一定有SO42—
B:滴入KMnO4酸性溶液,紫红色褪去,证明CH2=CHCH2CHO中一定有碳碳不饱和键
D:加入稀盐酸,产生无色并能使澄清石灰水变浑浊的气体,原溶液一定有CO32—或SO32—
What do you do at the weekends? Some people like to1 at home. But others like to go for a walk2 play football. My friend Jack works hard in a factory on3. At the weekends he always 4 different things. On Saturday he5 his car and on6 he goes with his family to a village by car. His uncle and aunt have a farm there. It's not a7 one, but there's always8 to do on the farm. The children help with the animals and give them their9. Jack and his wife help in the field. At the end of the day, they are all10 and want to have a big meat very much.
—I am going to the old people's home to celebrate Mrs. Green's______ birthday.