KanjiJLPT N3
Contain

contain, form, looks

Mnemonic

A roof built over an entire valley — imagine a dome so massive it could contain a whole canyon! The valley echoes inside, every sound bouncing under that enormous roof. Nothing escapes; everything is held within.
Additional thoughts
Picture a glass roof sealed over Yosemite Valley like a snow globe. The valley's vastness tests the roof's capacity, reinforcing the idea of containing something huge. Appearance ties in too: the valley's 'look' is preserved under glass.
Quick recall
A roof over a valley can contain an entire world.

Details

The keyword for 容 is contain. This kanji conveys the idea of holding something within, encompassing both the physical sense of containing or accommodating something inside a space and the more abstract sense of accepting or tolerating. It extends naturally to meanings related to appearance or form, as one's outward appearance is seen as the "container" of the inner self. The character is widely used in contexts involving capacity, acceptance, and looks or features.
On'yomi
よう
Kun'yomi
い.れる

Used in kanji