Main criteria of the sentence

1) Predication is a relation of the contemn of a sentence to the moment of speaking, it is based on the relation between the sentence and the predicate.

2) Modality – primary modality - modality of a sentence. Is the relation of the utterance to reality are stated be the speaker. Action can be real, unreal, desirable and so on.

Modality can be expressed by

- means of phonetics: stress, intonation

- lexical means: modal verbs, modal words, modal phrases

- grammar means: the system of moods and special constructions.

Lexical means of expressing modality

Modal words expressing assurance: certainly, surly, undoubtedly, of courts, really, indeed, in fact, doubtless, without doubt, beyond all doubt, positively.

Expressing strong supposition: accidentally, in all probability, apparently, obviously

Expressing probability: may be, probably, perhaps, possibly

Modal verbs express the speaker’s relation to the action, they may have expressed a subjective modal meaning.