i have been wacthing TV since 3 hours 5个同义句

来源：学生作业帮编辑：作业帮分类：英语作业时间：2024/08/25 01:54:02

the original sentence is grammatically wrong.
you want to say,you've been watching tv for 3 hours,or,you've been watching tv since 3 o'clock?
I've been watching tv for 3 hours.
I've been watching tv since 3 hours ago.
it is 3 hours since I've been watching tv.
I started watching tv 3 hours ago.
3 hours have passed since I started watching tv.

i have been wacthing TV since 3 hours 5个同义句 I have been down for two hours.改为同义句 I have been teaching English since 1986.改为同义句 They have been skating for five hours 同义句 They have been ska 初三同义句替换We have been waiting for many hours.We have been wait I have been watching TV for two hours.____is two hours____I I watch TV after I have dinner.的同义句 I have lived in Shenzhen since 1998.的同义句 I what TV for two hours every day同义句要两个不同的 They have been practicing the guitar for two hours.(改为同义句) I have been up since two hours ago.为什么这句话是对的?现在完成时不是不能跟过 I have been like this since last month 句意? 且请问been充当什么成分