1．___ apple four hundred years ago led to the law of gravity while ___ apple designed by Steve Jobs has changed our life greatly．
A．The; an B．An; an C．An; the D．The; 不填
2．—Thank you very much for your wonderful lecture, Mr．Brucel！
— .
A．It doesn't matter B．Don't mention it
C．That's very kind of you to say so D．I'm glad you've enjoyed it
