Lithuanian has two main grammatical numbers: singular and plural. There is also a dual number, which is used in certain dialects, such as Samogitian. Some words in the standard language retain their dual forms (for example "du" ("two") and "abu" ("both"), an indefinite number and super-plural words ("dauginiai žodžiai" in Lithuanian). Dual forms of pronouns used in the standard language are also optional. Although grammatically the dual number can be applied to any word, in practice it was used quite sporadically during the last century. The singular and the plural are used similarly to many European languages. Singular, plural and dual inflections of the same case always differ among themselves; no rule dictates how to form, for example, the plural inflection from the singular of the same case.