①如果再加上条件“BC=AD”,那么四边形ABCD一定是平行四边形;
②如果再加上条件“∠BAD=∠BCD”,那么四边形ABCD一定是平行四边形;
③如果再加上条件“AO=OC”,那么四边形ABCD一定是平行四边形;
④如果再加上条件“∠DBA=∠CAB”,那么四边形ABCD一定是平行四边形.
其中正确的说法是( )
A：①②
B：①③④
C：②③
D：②③④
﹣5的绝对值是（ ）
实行依法治国的重要前提是（ ）
***指出,华盛顿会议使中国“回复到几个帝国主义国家共同支配的局面”。华盛顿会议上签订的哪一条约导致了这一局面出现（ ）
In May, 1976, Gaynor was a nine-year-old girl and lived in North Wales. One day, on her way home from school, she saw a silver(银色的)object(物体)in a field not far from her home. The object looked like a saucer. Gaynor was very scared. She stayed behind the tall grass and watched the door of the strange object open. She saw two aliens wearing silver suits get out. Then they used something to examine(检测)the ground. They were short and had pink eyes. After about thirty minutes, the two aliens went back into the object. Then it took off. When Gaynor got home, she told her mother about this unusual experience, but her family decided to keep quiet about it. They didn’t want others to laugh at their daughter. However, 18 months later, Gaynor told her story to UFO scientists. They found out that Gaynor told the truth.
