I haven't heard from you for quite some time now.为什么后面要加个now呢?

i( ) from him since he leftA didn't receiveB haven't gotC haven't heard为什么? i haven't heard from him recently.这里 from him是表语吗. I haven't heard from him last week.I haven't heard from him _____ last week.(A)since (B) for (C)ago (D)before I()for six month A,have receievd Jonh's letterB,have heard from JONHc,haven't heard from JONH. i haven't heard from her for a long time什么时态?haven't heard 换成didn't hear、don't hear或者am not hearing 为什么? I haven't heard from him( )he went abroadA when D since 为什么选D 句型转换:I haven't heard from him for a long time. I haven't heard from him since last week .请问这句话对吗? I haven't heard from my sister ----------（recent).用所给单词的适当形式填空 I haven't heard from George (since the end of last year).(括号部分提问) 首字母填空I haven't heard from his e-mail r__________ I haven't heard from you for quite some time now.为什么后面要加个now呢? he said ,i haven't heard from my parents these days.变成间接引语 直接引语转间接引语 I haven't heard from my parents there days,said Mary. I haven't heard news from him for years.单句改错. 改错I haven't heard a letter from my penfriend for a few months. I haven't heard from Kelly for a long time .(同义句转换)I ----------from Kelly for a long time. 我还没收到他的来信的英语 I haven't heard from him yet 这里为什么是heard from而不是hear from?