|Look up that or those in Wiktionary, the free dictionary.|
- as a complementizer/subordinating conjunction. ("He asked that she go.")
- That can be omitted when used to introduce a subordinate clause—"he told me that it is a good read" could just as easily be "he told me it is a good read".
- That can be used in subordinate conjunctions describing a person or people when who(m) is problematic.
- to introduce a restrictive relative clause. ("The test that she took was hard.") In this role, that may be analyzed either as a relative pronoun or as a conjunction as in the first case; see English relative clauses: That as relativizer instead of relative pronoun. "That" is also used to replace and substitute the word "which" (subject) and "who" (person).
- as a demonstrative pronoun. ("That was hard.") (plural: those)
- as a demonstrative adjective. ("That test was hard.") (plural: those)
- as an adverb. ("The test wasn't that bad.")
In the first two uses the word is usually pronounced weakly, as /ðət/, whereas in the other uses it is pronounced /ðæt/.
In the Old English language that was spelled þæt. It was also abbreviated as a letter Thorn, þ, with the ascender crossed, ꝥ ( ). In Middle English, the letter Ash, æ, was replaced with the letter a, so that that was spelled þat, or sometimes þet. The ascender of the þ was reduced (making it similar to the Old English letter Wynn, ƿ), which necessitated writing a small t above the letter to abbreviate the word that ( ). In later Middle English and Early Modern English the þ evolved into a y shape, so that the word was spelled yat (although the spelling with a th replacing the þ was starting to become more popular) and the abbreviation for that was a y with a small t above it ( ). This abbreviation can still be seen in reprints of the 1611 edition of the King James Version of the Bible in places such as II Corinthians 13:7.
- "that (Definition of that in English)". Oxford Dictionaries. Retrieved 2018-07-07.