
提问人:网友f******g
发布时间:2022年3月12日 15:12
[问答题]
中国煤炭分类国家标准GB5751-86表征煤炭分类的指标是怎样的?


It is on Spring Festival Eve, ______ every one is celebrating the Chinese new year, ______ Senior 3 students in China can take a rest from their study.