形容詞 fruitless:

1. unproductive of success
   同義詞：bootless, futile, sleeveless, vain

1. All my efforts were fruitless.
   我所有的努力都白費(fèi)了。
2. So far the search for the missing boy has been fruitless.
   到目前為止，還沒有找到那失蹤的男孩。
3. His struggle with adversity is fruitless.
   他徒與不幸掙扎而毫無結(jié)果。
4. Their negotiation was fruitless.
   他們的談判沒有結(jié)果。

fruit.less

adj.（形容詞）
Producing no fruit.
不結(jié)果實(shí)的
Unproductive of success:
徒勞的：不產(chǎn)生益處或好處的：
例句：
a fruitless search.See Synonyms at futile
毫無結(jié)果的研究參見 futile

【引伸】
fruit.lessly
adv.（副詞）
fruit.lessness
n.（名詞）