By adding diacritic marks, you can modify the sound of some hiragana characters.

How to Write Diacritic Marks

	Two short strokes attached to the right shoulder of some symbols can change the voiceless /k/, /s/, /t/ and /h/ sounds to the respective voiced sounds of /g/, /z/, /d/ and /b/ (e.g., か ⇒ が ).
	A small circle attached to the right shoulder of the /h/ column symbols changes the /h/ sound to the /p/ sound (e.g., は ⇒ ぱ ).

Click on each box and hear how the diacritical marks change the sound of each hiragana column.

Hiragana with Diacritics Marks

じ and ぢ are pronounced with the same /ji/ sound, as in jeep (not /di/ as in deep). Likewise, ず and づ share the same /zu/ sound, as in zoo (not /du/ as in do). However, these characters are not interchangeable. Each word has only one correct spelling. In general, じ and ず are used far more frequently than ぢ and づ. When typing Japanese on a computer,
the following hiragana conversions will occur.

How romanized text is converted to hiragana

If you type	you will get
sizuka or shizuka siduka or shiduka	しずか しづか	ok (This means "quiet.") misspelled
zisho or jisho disho	じしょ ぢ し ょ	ok (This means "dictionary.") misspelled
tuduku or tsuduku tuzuku or tsuzuku	つ づ く つ ず く	ok (This means "continue.") misspelled
hanadi hanazi or hanaji	は な ぢ は な じ	ok (This means "nosebleed.") misspelled