language. English is the main language used in Singapore. As English links the different races and ethnic groups, a group with diverse races and ethnicities communicate using English. Most of the population can speak, read and write in English. In addition to English, many Singaporeans can speak their respective ethnic language like Mandarin Chinese fairly well, as it is a compulsory subject in school. In Chinese communities, the older generation usually speak their own language like Hakka and Hokkien besides Mandarin and/or English. Thailand: Thai is the main and sole official language in Thailand. There are different dialects such as Phitsanulok, Ayutthaya, Suphan Buri (traditional dialect), Thonburi, but Standard Thai is influenced by Thai Chinese in Bangkok, Isan which is influenced from Lao and widely used in the northeastern area, Southern Thai is spoken in the southern provinces, Northern Thai is spoken in the provinces that were formerly part of the independent kingdom of Lanna. Karen languages are spoken along the border with Burma, Khmer near Cambodia (and previously throughout central Thailand), and Malay in the south near Malaysia. The Thai hill tribes speak numerous small languages. Also, there is a big population of Chinese descent people in Thailand and the old generation often use Teochew as well as Hakka as their first language. The new generation tends to speak them as a second language or some may not know it at all. Vietnam: Vietnamese is the official language, and English is the most commonly used and studied second language, especially in education, international relations, and the media. In addition, French is spoken by a small minority of people and elders as it used to be the most common second language. The right to use own language, also in courts, is foreseen in the constitution. Western Asia Bahrain: Arabic is the official language, and English is the most commonly used and studied second language, especially in education, international relations, and the media. In addition, Persian and Urdu are widely spoken. In Iran, Persian is the sole official language, but Azerbaijani (along with related varieties such as Qashqa'i and Kalaj) has upwards of 15 million speakers. Other minority languages include Kurdish, Turkmen, and Balochi. Assyrian is spoken by a Christian minority in the vicinity of Urmia. In the southwestern Iranian province of Khuzestan, most people speak Khuzestani Persian, Khuzestani Arabic, and Standard Persian, sometimes in addition to their own community languages