Manually-Coded English (MCE) is a type of sign system that follows direct spoken English. The different codes of MCE vary in the levels of directness in following spoken English grammar. There may also be a combination with other visual clues, such as body language. MCE is typically used in conjunction with direct spoken English. Manually-Coded English systems MCE has been labeled many terms—including Signed English, Manually-Coded English, Sign Supported Speech, and Sign Supported English, none of which specify the degree to which the user is attempting to sign specific English vocabulary or correct grammar. MCE differs from American Sign Language which has a very different grammar (including word order) than English. Deaf sign languages make use of spatial relationships, facial expression, and body positioning, while the degree to which a MCE-user incorporates these features depends on their proficiency in doing so. However, in an invented system such as Signing Exact English (SEE), the use of manual features is described in the first and subsequent issues of the SEE Dictionary and users must use facial expression, directionality, body position, emphasis and so forth to score well on certification tests such as the Educational Interpreter Performance Assessment and the Educational Sign Skills Evaluation. Although there is no research to support the notion, many in the field of deaf education believe that comprehensibility of such MCE has been compromised in practice. Experience can improve the degree to which the information coded in English (morphologically as well as syntactically) is successfully communicated manually, and research in this regard can be found by searching Wikipedia for Signing Exact English. There is no research to suggest that those who are motivated to sign the complete grammar of English cannot do so if they learn the vocabulary, desire to sign proficient, grammatically-correct English, and are observed and coached to do so. In English-speaking countries, it is common for users of Deaf sign languages to code-switch into a form of MCE when conversing with someone whose dominant language is English, or when quoting something from English. MCE is also sometimes favored by hearing people, for whom a manual version of their own language is much easier to learn than a deaf sign language. In education The different forms of manually coded English were originally developed for use in the education of deaf children, as their literacy in written English has been typically low compared to their hearing peers.