Radical 丶

5 strokes

heart 心 (161) + slide (34b) = inevitably 必

It is natural to think of this as “heart” together with an extra stroke, but watch the stroke order.

[必要 (101) bìyào necessary]

[不必 (9) búbì don’t need to]

In the theme park there is a huge slide through the heart of the forest — inevitably it gets clogged up (with twigs and leaves). / Each day the dwarf has to send his beaver down the slide to clean it out.