已知:A=3a2﹣4ab,B=a2+2ab.
John ________ play the guitar, but he wants to join the guitar club.
元素名称
钠
钙
铝
氢
氯
氧
硫
具备下列哪一特征的植物不适宜生活在如图所示生物生活的环境中( )