Born into a family with three brothers, David was ________ to value the sense of sharing.
——I’d like to invite you to a concert this evening.
——Thank you, but I’ll be free I’m not sure at the moment.
下列制取硫酸铜的实验设计中，能体现“经济、高效、环保”的最佳方案是()
第二次工业技术革命，世界上形成的两大工业地带是:()
下列各组词语中加点的字的读音，与所给注音全都相同的一组是
