现在式转换为过去式I think I was have a good time on this vacation.这句话是标准的过去式吗?

现在式转换为过去式I think I was have a good time on this vacation.这句话是标准的过去式吗? 宾语从句的时态I thought that 后面是跟现在式还是过去式?若为过去式,情态动词must,can怎么办? I think he has some money 转换为否定句 I think english is fan变过去式 S W I M 的过去式 I think I should have a talk with her,____ ____?(转换为反意疑问句) I think I should have a talk with her,_.(转换为反意疑问句) 英语四个时态个两篇作文,每篇不少于五十个单词过去式、现在式、一般式i、将来式, 怎样区分过去式,现在式. 过去式和现在式是什么? 西语：vestirse和sentarse的简单过去式?三单vestirse的过去式是se vistió和现在式一样的把e变成i,那为嘛sentarse的过去式不是e变ie,变成se sientó而是se sentó? 句型转换：I can't speak French.I think.(合为一句,意思不变) I ____ ____ I ____ speak French. I think I should talk with her.（同义句转换.） I think I should ( ) ( ) talk with her.I think I should talk with her.同义句转换.I think I should ( ) ( ) talk with her. I think that subiect is boring(同义句转换） I（ ）think that subject is( ) I don't think they are in.(同义句转换)I don't think they are ( ) ( ). I think it helps.I think it（）（）.句型转换 I live near the fire station,so i can often hear the sound of a _____(消防车)看清楚形式阿..要用过去式就用过去式,用现在式就用现代式. I play football with my friend 转换成过去式：转换成现在进行时：