Question

futile 【FUTILE】All his attempts to unlock the door were futile, because he was using the wrong key.他尝试所有打开门的方法，但却无效，因为他用错了钥匙。【重点词汇】futile adj. 无效的 反: useful

Accepted Answer

['fjuːtl] 
futileproducing no result or effect
When something fails to deliver a useful result, you can call it futile. Hopefully all the time you're spending studying vocabulary won't turn out to be futile!
Futile comes from the Latin futilis, which originally meant "leaky." Although we use futile to talk about more than buckets, the image of a leaky vessel is a good illustration of the adjective. Pouring water into a leaky bucket is futile.  Your exercise program will be futile if you don't stop chowing down on chocolate. Futile is fancier than its synonym useless. Other synonyms are fruitless or vain. The i can be either short (FYOO-t'l) or long (FYOO-tile).
All forms of 'futile' will appear on average once every 586 pages.futilefutilelyfutility

Front	futile
Pron	['fjuːtl]
Back	【FUTILE】 All his attempts to unlock the door were futile, because he was using the wrong key. 他尝试所有打开门的方法，但却无效，因为他用错了钥匙。【重点词汇】 futile adj. 无效的反: useful
Vocab	futileproducing no result or effect When something fails to deliver a useful result, you can call it futile. Hopefully all the time you're spending studying vocabulary won't turn out to be futile! Futile comes from the Latin futilis, which originally meant "leaky." Although we use futile to talk about more than buckets, the image of a leaky vessel is a good illustration of the adjective. Pouring water into a leaky bucket is futile. Your exercise program will be futile if you don't stop chowing down on chocolate. Futile is fancier than its synonym useless. Other synonyms are fruitless or vain. The i can be either short (FYOO-t'l) or long (FYOO-tile). All forms of 'futile' will appear on average once every 586 pages. futile futilely futility

Futile Leaky Fjuːtl Attempts Unlock Door Wrong Key