A:to be referred to; to be e-mailed
B:referring to; e-mail
C:referred to; be e-mailed
D:being referred to; being e-mailed
Did you often talk with your friends in English?
有机物分子中基团间的相互影响会导致化学性质不同.下列叙述不能说明上述观点的是( )
已知f(x),g(x)都是定义在R上的函数,且满足以下条件:①f(x)=ax•g(x)(a>0,且a≠1);②g(x)≠0;③f(x)•g′(x)>f′(x)•g(x).若f1g1+f-1g-1=52,则a等于( )
下列有关运动和力的描述或解释正确的是( )