Jeg ved, hvor farligt det kan være at være sammen med hende.
- I know how dangerous it can be to be with her.
Tom siger, at han ved, hvor svært det vil være at gøre det.
- Tom says he knows how difficult it'll be to do that.
Каким хорошим учёным должен быть автор, чтобы написать такую превосходную книгу!
- What a good scholar the author must be to write such a splendid book!
Я не знаю, когда экзамен. Может быть завтра.
- I don't know when the exam is. It may be tomorrow.