For example: "There is a heaven"; "There are two cups on the table"; "There have been a lot of problems lately". It can also be used with other verbs: "There exist two major variants"; "There occurred a very strange incident". The dummy subject takes the number (singular or plural) of the logical subject (complement), hence it takes a plural verb if the complement is plural. In informal English, however, the contraction "there's" is often used for both singular and plural. The dummy subject can undergo inversion, "Is there a test today?" and "Never has there been a man such as this." It can also appear without a corresponding logical subject, in short sentences and question tags: "There wasn't a discussion, was there? There was." The word "there" in such sentences has sometimes been analyzed as an adverb, or as a dummy predicate, rather than as a pronoun. However, its identification as a pronoun is most consistent with its behavior in inverted sentences and question tags as described above. Because the word "there" can also be a deictic adverb (meaning "at/to that place"), a sentence like "There is a river" could have either of two meanings: "a river exists" (with "there" as a pronoun), and "a river is in that place" (with "there" as an adverb). In speech, the adverbial "there" would be given stress, while the pronoun would not – in fact the pronoun is often pronounced as a weak form, . Other pronouns in English are often identical in form to determiners (especially quantifiers), such as "many", "a little", etc. Sometimes, the pronoun form is different, as with "none" (corresponding to the determiner "no"), "nothing", "everyone", "somebody", etc. Many examples are listed as indefinite pronouns. Another indefinite (or impersonal) pronoun is "one" (with its reflexive form "oneself" and possessive "one's"), which is a more formal alternative to generic "you". The basic form of an English verb is not generally marked by any ending, although there are certain suffixes that are frequently used to form verbs, such as "-ate" ("formulate"), "-fy" ("electrify"), and "-ise/ize" ("realise/realize"). Many verbs also contain prefixes, such "un-" ("unmask"), "out-" ("outlast"), "over-" ("overtake"), and "under-" ("undervalue").