bridge (replacement for teeth)

natural environment

(computing) character whose appearance may depend on a user's environment, or a character which may be absent from a user's environment, i.e. character set incompatibility

environmental pollution

謀: plan, scheme, plot (especially malicious one)

何事: what sort of matter; unspecified matter

lesson

鬼事: tag (game)

東琴: (music) a six-stringed koto or zither used to perform kagura music, more common in ancient times

(onomatopoeia) with the sound of something mechanical moving