My friend,i'll tell u the how to tell.
如書上寫的：I didn't dare to open the window until the window had to be shut.
這里的dare便是實意動詞,為vt.及物動詞.
1.情態(tài)動詞dare 沒有人稱的變化.
2.情態(tài)動詞dare 通常用在否定句中.
3.如果是實義動詞問,回答也用實義動詞.
4.I did’t dare (to) speak to him again.= I dare not speak to him again.
dare do 是情態(tài)動詞
dare to do是實義動詞
..not dare ...是實義動詞He didn't dare ...
...daren't 是情態(tài)動詞 He dared not ...