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wasteful; a waste
too good; more than one deserves; unworthy of
impious; profane; sacrilegious
食べ物を捨てるのは勿体ない。
It's wasteful to throw away food.
こんな才能を無駄にするのは勿体なかった。
It's a waste to let such talent go to waste.
勿体ないから最後まで使おう。
Let's use it until the end because it's wasteful not to.