Helping verbs are not unique to English. Also called “auxiliary verbs,” helping verbs are common in analytical languages like English. (An analytical language has lost most of its inflexions.) Auxiliaries are used with main verbs to help express grammatical tense, mood, and voice.
tense: forms or modifications (or word-groups) in the conjugation of a verb to indicate time (past, present, or future).
mood: a form or set of forms of a verb in an inflected language, serving to indicate whether the verb expresses
voice: a category used in the classification of verb forms serving to indicate the relation of the subject to the action. For the difference between active and passive voice, see “Verbs Voice.”
A highly inflected synthetic language like Latin, on the other hand, combines tense, mood, and voice into a single compounded word.
Take, for example, the English sentence “I had sung.” Each of the three words conveys a significant piece of information. The free-standing pronoun I