The stroke direction and angles are important factors in distinguishing katakana symbols.
/so/
/shi/
The last strokes of ソ (/so/) and ン (/nn/) are written in the opposite directions as shown on the left. To emphasize the direction of the last stroke, we often put a small hook at its beginning. The following animation may help you associate katakana ソン with hiragana そん.
vs.
/tsu/
/shi/
Similarly, the last strokes of ツ (/tsu/) and シ (/shi/) are written in the opposite directions as shown on the left. To emphasize the direction of the last stroke, we often put a small hook at its beginning. The following animation may help you associate katakana ツシ with hiragana つし.
vs.
The angle of strokes is also an important factor in distinguishing
symbols like ソ (/so/)
and リ (/ri/)
. The two strokes in ソ are slanted inwardly while the strokes in リ are parallel to one another (initially).