The modal word, occupying in the sentence a more pronounced or less pronounced detached position, expresses the attitude of the speaker to the reflected situation and its parts. Modal words stand in a special relation to the sentence. They are not sentence members, since giving an evaluation of the entire situation presented in the sentence, they stand on the outside. For instance, in the sentence Perhaps, dimly, she saw the picture of a man walking up a road (Christie) the modal word perhaps is not a sentence member, but if we remove it, the meaning of the utterance will change – it will be just a statement of the fact.