___________ no gravity, there would be no air around the earth, hence no life
A.If there had been
B.If there was
C.Had there been
D.Were there
第9题
A、重力是万有引力中特殊的一种力,重力属于万有引力; Gravity is a special force in the Universal Gravitation, Gravity belongs to the Universal Gravitation;
B、重力就是万有引力,万有引力就是重力; Gravity is Universal Gravitation, and Universal Gravitation is Gravity;
C、重力不是万有引力,重力与万有引力是两种力; Gravity is not Universal Gravitation, Gravity and Universal Gravitation are two kinds of forces;
D、以上都不对; None of the above is true;
为了保护您的账号安全,请在“上学吧”公众号进行验证,点击“官网服务”-“账号验证”后输入验证码“”完成验证,验证成功后方可继续查看答案!