... features such asauxiliary verbs”, Modal verb have more defects lack some uniquecharacteristics as follows :- No “TO” in prototypes and when verb follows. And modal verbs areused together with ... serve as ordinary verbs in a given sentence. The modal verbs are: CAN, COULD, MAY, MIGHT, MUST, SHALL, SHOULD,OUGHT TO, WILL, WOULD.http://www.learnenglish.de/grammar/verbmodal.htm(Please ... “All the auxiliary verbs except be, do andhave are called modals. Unlike other auxiliary verbs modals only exist in theirhelping form; they cannot act alone as the main verb in a sentence....