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clumsy; unskillful
拙劣な模倣はすぐに見破られてしまう。
A clumsy imitation is quickly seen through.
交渉の進め方が拙劣で契約を逃した。
The negotiation was handled so poorly that the contract was lost.
拙劣な言い訳が彼の信用を失墜させた。
His clumsy excuses caused him to lose credibility.