Four more consonants, and the shape of a block

Two ways to build a block

ㅂ ㅅ ㅈ ㅎ complete the basic consonants. And the rule that puts them into blocks is short: a vowel with a standing long line goes to the RIGHT of the consonant, and a vowel with a lying long line goes UNDER it. That is the whole geometry of Korean writing.

Four strokes and two. The first is two posts, a bar and a floor; the second is a narrow gap.

And two more: the second is the first of this pair with a lid, and the last one wears a hat and a circle.

The same consonant twice, with a standing vowel and then a lying one. Watch where it moves.

바다the sea

모자a hat

Because the arrangement follows the vowel, a block always fills the same square whatever it contains. That is why Korean text lines up so neatly, and why you can tell where one syllable ends and the next begins without a single space.