unavailing
adjective formal or literary uk/ˌʌn.əˈveɪ.lɪŋ/ us/ˌʌn.əˈveɪ.lɪŋ/
徒劳的，无成果的
When an attempt to do something is unavailing, it is unsuccessful or has no positive effect.
Diplomatic efforts at peace-making have so far proved unavailing. 调停争端的外交努力到目前为止被证明是徒劳的。
Synonyms: abortive fruitlessfutileineffectual unsuccessful
Opposite: successful