总觉得这道题怪怪的,如果是dated at XXX years ago, 还好理解,不过有了这个old,感觉应该用dated to be。虽然GWD那道题也是old。大家好好想一下,dated to be XXX years old,这里XXX years old并非像大家所说的是一个点。理解一下,应该是表明这个东东 is XXX years old。总是有种不爽的感觉。唉!大家再想想。
Rock (samples) taken from the remains of an asteroid about twice the size of the 6-mile-wide asteroid eradicated the dinosaurs (has) been dated to be 3.47billion years old and thus( is )evidence of the earliest known asteroid impact on earth 。