it seems that句型转换的问题1、It seems that she was here last week.——She seems to HAVE BEEN here last week.2、 It seemed that she knew everyone there-——She seemed to KNOW everyone there.我想知道转换后第一句为什么用have

来源:学生作业学帮网 编辑:学帮网 时间:2024/05/30 08:41:33

it seems that句型转换的问题
1、It seems that she was here last week.
——She seems to HAVE BEEN here last week.
2、 It seemed that she knew everyone there-
——She seemed to KNOW everyone there.
我想知道转换后第一句为什么用have been,第二句为什么用know.
it seems to be后可接名词性从句吗?

1.seem to do sth中,seem后面加的是不定式的一般形式;
而seem to have done sth中,seem后面加的是不定式的完成形式.
后者表示不定式的动作发生在seem动作之前.
2.第一句变化中,seems为一般现在时,即seem发生在现在,而was here为一般过去时,发生在过去.
也就是说不定式to be here发生在seem之前,所以使用其完成形式,即变成了:seems to have been here;
而第二句变化中,seemed和knew都是用过去式,表明这两个动作同时发生,所以只需要用seem to do sth即可.
3.It seems to be + 表语 结构中,to be经常可以省略,尤其是加表语从句时,此时一般没有to be.
所以It seems后面可以加名词性从句,it seems to be后面不加.
其表语从句一般由that,as if或as though引导.
如:It seems that you are tired.看起来你似乎累了.
It seems as if/though it is going to rain.看起来似乎要下雨了.
如果你满意我的答案,这是对我们答题者劳动的尊重,多谢!

第二句的seem用了过去时.

因为第二句的seem用了过去时.