Ko
(
コ
)
tsu
(
ツ
)
Ko
(
コ
)
tsu
(
ツ
)
App Store
Google Play
Vocabulary
Katakana
Basic sounds
セ
New
セ
セ
se
Katakana · Basic sounds
Again
1
Hard
2
Good
3
Easy
4
Previous word
Space flip · 1–4 grade · ← → move
Next word