跟动词不定式，can't wait to do sth.

can't wait to do sth意思是“等不及做某事”、“迫不及待做某事”的意思，带主观情感。如：

I can't wait to see her again.我迫不及待地想要再次见到她。

过去式是couldn't wait to do sth.

On Christmas Day, the children woke up very early,and couldn't wait to open the presents in their stockings.圣诞节那天，孩子们醒得很早，急不可耐地打开长袜中的礼物。