From top: roof 宀, heart 心, eye 罒, city block 丁 (Here: a nail as at 'to strike' 打)
Mnemonic
(Good work of the roofer:) The roof was built with the heart (= loving work) and the eyes (= careful & clean) and nails, so that it is rather preferable and I am peaceful.
The Radical yongashira shows the picture of an eye with a central pupil ロ, whereas 'eye' is also: 目. This radical is sometimes seen as a net for fishing.
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