In English, the main instrument for expressing speaker's attitude toward the content of his utterance are the modal verbs. In Spanish, the center of the modal system is formed by verbal moods that can co-occur with modal verbs.
We may distinguish two levels of this co-occurrence: cooperation and competition. The fact that Spanish modal verbs can be subjected do tense and, more importantly, modal inflection offers to Spanish speakers a possibility of double modalization which is, generally, impossible in English (cooperation).
On the other hand, the strongly fusional character of the Spanish verbal system often leads to a complete omission of modal verbs and their substitution by other resources for expressing modality, especially, by the subjunctive (competition). Our research provides a contrastive study of English constructions that contain a modal verb and their respective Spanish equivalents.
Using the parallel corpus InterCorp, we analyze a wide range of Spanish translations of English modals, concentrating on their frequency, on the criteria that lead to their selection and on the level of their cooperation / competition with other modal resources (complete substitution of the English modal by the subjunctive, conditional or epistemic future, modal and tense inflection of the modal verb or its combination with lexical expressions of modality). This analysis enables us to outline some of the main differences between Spanish and English modality in general and helps us to determine the position of Spanish modal verbs in the Spanish modal systems.
It also shows to what extent a concrete modal flavor expressed in English can be translated into Spanish, reflecting, thus, their (in)stability.