[译] 他们的实验无甚价值。
[误] The experiment made by them is invaluable.

[正] The experiment made by them is valueless.
[注] 形容词 valuable (worth a lot of money; having great value) 其反义词是 valueless 或 worthless, 而不是 invaluable (= very useful; priceless 意为"极有用的"、"无价的")，如：The oil paintings of Leonardo da Venci are invaluable. 达·芬奇的油画是无价之宝。