Classical compounds and neoclassical compounds are compound words composed from combining forms (which act as affixes or stems) derived from classical Latin or ancient Greek roots. New Latin comprises many such words and is a substantial component of the technical and scientific lexicon of English and other languages, including international scientific vocabulary. For example, combines with to form biography ("life" + "writing/recording"). A vowel usually facilitates the combination: in biography, the interfix , in miniskirt, the interfix . This vowel is usually regarded as attached to the initial base (bio-, mini-) rather than the final base (-graphy, -skirt), but in forms where it is conventionally stressed, it is sometimes shown as attached to the final base (-ography, -ology). If, however, the final base begins with a vowel (for example, -archy as in monarchy), the mediating vowel has traditionally been avoided (not *monoarchy), but in recent coinages it is often kept, sometimes accompanied by a hyphen (auto-analysis, bioenergy, hydroelectricity, not *autanalysis, *bienergy, *hydrelectricity).