Modal verbs are commonly used to express various degrees of certainty from near certainty to uncertainty through possibility or probability. So in English : 1 - She must be in her room 2 - She can't be in her room 3 - She should be in her room 4 - She may be in her room 5 - She could be in her room 6- She might be in her room I think such gradations could be set up in French or German with müssen , dürfen, können, mögen, sollen. What about Dutch ? Is it possible to make out a similar kind of scale with verbs as moeten , zullen , kunnen or others ? Thanks a lot for your explanations.