do sth. which one has done before是什么意思？

• ultra
• neck
• 来源英语
• aspect
• disappointed
• 领域英语
• repeat
• 队长的英文
• maths
• 局外人英文
• conflict
• prompt
• polite
• panicked
• fake
• crayon
• 长颈鹿英语怎么说
• various
• 抛弃英文
• modernize
• 确认英文
• brat
• bothering
• tomato
• volume
• cheese
• 参与者英文
• ticket
• algiers
• amazing

• juice
• dragon
• emergency
• passage
• 导师英文
• front
• sweater
• searches
• 缺陷英文
• organizations
• banger
• 呼吁英语
• narrow
• 参数英文
• droplets
• approaches
• peeping
• general
• candy
• toxicity
• explore
• silver
• 权限英文
• erased
• scared
• autumn
• intermission
• cloud
• text
• chess翻译

• truce
• trustworthy
• tumult
• turbot
• turf
• turmoil
• tutorial
• tweezers
• twig
• tyrannical
• ubiquitous
• ultimatum
• uncalled
• uncap
• unconcerned
• undeniable
• undercharge
• underwrite
• undue
• undulate
• unduly
• uneven
• ungainly
• unicorn
• unilateral
• unofficial
• unravel
• unthinkable
• untimely
• untold