確 (Kanji for make certain)

Onyomi

KAKU

Please make certain that the swan's COCK is hard as a rock. (the swan with the hardest COCK gets to wear the crown)

(it's not how I personally would decide the future of the monarchy, but then I'm not Japanese)

たし*か ( な )

probably
★★★☆☆

確認(かくにん) する

double-check ★★★★☆
確 (make certain) + 認 (admit) = 確認 (double-check)

to double-check something.

確率(かくりつ)

probability ★★☆☆☆
確 (make certain) + 率 (ratio) = 確率 (probability)

確実(かくじつ)

certainty ☆☆☆☆☆ NP
確 (make certain) + 実 (truth) = 確実 ( certainty)

certainty. This is never used as a verb. You'd never say 確実する。

TELLING APART THE SWAN MOTHERFUCKERS:

I recommend you get STRONGER.

You SEE things from your point of view .

But TREES have rights,to not get cut down. Or so they say.

Make ROCK SOLID CERTAIN that your kanji are correct.