are always voiceless, aspirated in syllable onset (except in clusters beginning with ), and sometimes also glottalized to an extent in syllable coda (most likely to occur with , see T-glottalization), while lenis consonants are always unaspirated and un-glottalized, and generally partially or fully voiced. The alveolars are usually apical, i.e. pronounced with the tip of the tongue touching or approaching the roof of the mouth, though some speakers produce them laminally, i.e. with the blade of the tongue. Consonant examples The following table shows typical examples of the occurrence of the above consonant phonemes in words, using minimal pairs where possible. Sonorants The pronunciation of varies by dialect: Received Pronunciation has two main allophones of : the clear or plain (the "light L"), and the dark or velarized (the "dark L"). The clear variant is used before vowels when they are in the same syllable, and the dark variant when the precedes a consonant or is in syllable-final position before silence. In South Wales, Ireland, and the Caribbean, is usually clear, and in North Wales, Scotland, Australia, and New Zealand it is usually dark. In General American and Canada, is generally dark, but to varying degrees: before stressed vowels it is neutral or only slightly velarized. In southern U.S. accents it is noticeably clear between vowels, and in some other positions. In urban accents of Southern England, as well as New Zealand and some parts of the United States, can be pronounced as an approximant or semivowel () at the end of a syllable (l-vocalization). Depending on dialect, has at least the following allophones in varieties of English around the world (see Pronunciation of English /r/): postalveolar approximant (the most common realization of the phoneme, occurring in most dialects, RP and General American included) retroflex approximant (occurs in most Irish dialects and some American dialects) labiodental approximant (occurs in south-east England and some London accents; known as r-labialization) alveolar flap (occurs in most Scottish, Welsh, Indian and some South African dialects, some conservative dialects in England and Ireland; not to be confused with flapping of and ) alveolar trill (occurs in some very conservative Scottish dialects and some Indian, South African and Welsh accents) voiced uvular fricative (occurs in northern Northumbria, largely disappeared; known as the Northumbrian burr) In most dialects is labialized in many positions, as in reed and tree ; in the latter case, the may be