有质量的物体周围存在着引力场。万有引力和库仑力有类似的规律，因此我们可以用定义静电场强度的方法来定义引力场的场强。由此可得，与质量为M的质点相距r处的引力场场强的表达式为E_G=____________（万有引力恒量用G表示）。

His jewelry shop is said ____ and he can't help but____ the fact.[ ]

A. robbing; to accept            

B. to rob; accepts

C. to have robbed; accept        

D. to have been robbed; accept