某气体R在氧气中燃烧,只生成H2O和SO2,
读“我国四大盆地甲、乙、丙、丁分布示意图”,
My sister likes playing_____guitar and she also likes playing______soccer.
富兰克林·罗斯福指出:“并非追求利润的自由企业制度已在这一代人中失败,而是尚未经受考验。”这表明( )