Usually used as a plural:scissors,pincers,glasses,shorts,trousers,suspenders....If there is a unit word, the single and plural forms of the unit word determine the single and plural forms of the verb.
A few nouns can be either singular or plural:whereabouts/dramatics...
A noun ending in -ings, usually plural.Exception: "tidings" can be used in both singular and plural
Subsequent singular and plural forms of verbs depend on whether these nouns are used as singular or plural:barracks,headquarters,means...
A few nouns have different meanings in the singular and plural:odds,remains...