since two years ago 中但是ago不是标志过去式吗?不矛盾吗

since two years ago 中但是ago不是标志过去式吗?不矛盾吗 "two years ago "不是表过去时吗?为什么可以与现在完成时连用?(since two years ago)而 SINCE TWO YEARS AGO的同义句 He has died since two years ago.这句话语法有错吗? I started to learn English since two years ago.问问大家这句话有语法错误吗 the swimming club opened two years ago（用since two years ago She has swum since half an hour ago.不是说ago不能用在完成时吗? he has left since three years ago可以用吗 Mr green has ()us English since two years ago They ___(live) there since two years ago How long ___ your mother ___?Since two years ago. Since they(visited/have visited)hangzhou two years ago,they(