Some observers consider non-manual behaviors in Polish Sign Language (PSL) as only to 'express emotions'. The review of the major findings of linguistic research on the non-manual components of PSL shows that PSL grammar not only relies on space, hand shape and movement, but it may also be expressed by non-manual signals: signer's face, head, torso, and eye. These behaviors play important linguistic roles in creating manual sentences. The authors' study illustrates how different combinations of non-manual components signal different kinds of single sentences: (1) general questions, (2) detailed questions, (3) negated statements, (4) negated questions, (5) asserted statements, (6) sentences with topical segments, and (6) commands.