Malaysian English (MyE), formally known as Malaysian Standard English (MySE), is a form of English used and spoken in Malaysia. It is distinct from Malaysian Colloquial English, which is also known as Manglish. According to English Proficiency Index, about 60% of Malaysians are proficient in English. Due to the lack of use of English and the lack of English medium schools (which were phased out after the 1969 race riots) to accommodate English speakers, the language has been in rapid decline since the 1970s.
According to The Encyclopedia of Malaysia: Languages & Literature, p 61, English in Malaysia has been categorized into three levels: the acrolect, mesolect and basilect. The acrolect is near-native. Only those educated in core English-speaking countries from early schooling up to university may be found to speak the acrolect variety, and only a small percentage of Malaysians are proficient in it. As with other similar situations, a continuum exists between these three varieties and speakers may code-switch between them depending on context. Most academics, professionals, and other English-educated Malaysians speak mesolect English. Malaysian English belongs to mesolect, and it is Malaysian English that is used in daily interaction.
Manglish refers to the colloquial, informal spoken form of Malaysian English. It is the most common form of spoken English on the street, but is discouraged at schools where only Malaysian Standard English is taught. Imported words are actually minimal except for just a handful of common non-English nouns and verbs in Malaysia. The use of Manglish is therefore a style-based decision. Colloquialisms exist that are not common outside of Malaysia, which are used colloquially as substitutes in other languages in Malaysia. Using Malay, or Chinese grammar in conjunction with English words, is often done quite spontaneously, sometimes even for comic effect.