It is _____ dark outside. (Too/Very)
Both 'very' and 'too' can be used.
It is very dark outside. It means that it is extremely dark.
It is too dark outside. It has a negative connotation: it is too dark to do something.
It is very dark outside. It means that it is extremely dark.
It is too dark outside. It has a negative connotation: it is too dark to do something.