依次填入下列各句横线处的成语，最恰当的一组是 ①特别是傍近铁路的河堤，更是牢固严实， ，简直连个蚂蚁洞的孔隙也没有给洪水留下。②我军万船齐发，攻破“千里江防”，很快就占领了蒋介石自以为防守得 的南京城。③潮汛已经过去了，大坝仍然屹立不动， 。

一_______your brother have a basketball—Yes, but an old one.

This new method ofteaching for the time being in our school Itwill be carried out all________over the city

Alice, why didn’t you come yesterday?—I ____, but I had an unexpected visitor

The place _______ interested me most wasthe Gnat Wall