They_____us since five o'clock this morning.(A)are helping(B)have_英语解答

They_____us since five o'clock this morning.
(A)are helping(B)have beng helping(C)have beng helped
(D)have helped

人气：334 ℃　时间：2020-03-29 16:46:40

解答

b 因为是从今天早上五点到现在还在帮助我们
而且有since 提示
所以用现在完成进行时