一David has been away for more than 25 days．
--I miss him very much．You know,25 daysshort．
A．is B．isn’t C are D．aren’t
答案B
本题题意为“David已经离开超过25天了”“我们非常想念他,你知道,25天并不短.”时间、金钱作主语,谓语动词be要用单数形式,因此答案为B.