useless
/ˈjuːslɪs/adjective
1- not fulfilling or not expected to achieve the intended purpose or desired outcome无用的, 无效的：
a piece of useless knowledge.
无用的知识
we tried to pacify him but it was useless.
我们试着抚慰他, 但一切都是徒劳的。
1.1
- informal having no ability or skill in a specified activity or area〈非正式〉（特定活动或领域中）无能力的; 没有技能的：
he was useless at football.
他不会踢足球。
派生词