Translation guide
In Japanese writing, a long vowel is indicated by a special mark in kana, or by certain kana combinations. The method depends on the writing system: hiragana, katakana, or romaji.
How to write a long vowel in katakana
In katakana, a long vowel is indicated by a long dash-like mark called 長音符 (chōonpu). It extends the preceding vowel sound.
パーティー
party
How to write a long vowel in hiragana
In hiragana, a long vowel is written by adding the corresponding vowel kana: あ for a, い for i/e, う for u/o. For e, い is usually used, but sometimes え; for o, う is usually used, but sometimes お.
How to write a long vowel in romaji (Latin alphabet)
In romaji, long vowels are often indicated by a macron (e.g., ā) or by doubling the vowel (e.g., aa). The macron is standard in Hepburn romanization, while doubling is used in some systems or when macrons are unavailable.