最常见X线不显影的结石（）
A.尿酸结石
B.氨酸结石
C.磷酸盐结石
D.碳酸钙结石
E.黄嘌呤结石
参考答案：A
根据汉语提示，用词组的适当形式填空。
1. Xiao Li, don't throw your bag on the ground. Please _______ it _______. (收好)
2. The children found the picnic was _______ _______ (不再) under the tree.
3. The mother often _______ her children _______ (阻止她的孩子们) playing football in the street.
4. We Chinese people are all (感到自豪) our country.
5. My new shoes are _______ _______ (穿破了).
（）年，中国广告恢复全面启动，被成为中国的广告元年。
A.1979
B.1980
C.1981
D.1983
