a trace of sth
用 a trace of 表示极少的量或轻微的迹象，后接不可数名词或抽象名词。
There was a trace of sadness in her voice.
她的声音里有一丝伤感。
痕迹；踪迹；迹象
微量；一丝；些许；（电路板上的）导线；线路；走线；追踪；追溯；描摹；（干旱地区的）小径；土路；（寻找丢失邮件等的）查询
a mark or sign left by someone or something that was present
追踪的行为。
An act of tracing.
刚刚可检测到的数量
a just detectable amount
对丢失物品(如信件或快递包裹)的查询。
An enquiry sent out for a missing article, such as a letter or an express package.
某物曾存在的迹象
an indication that something has been present
作为人或动物经过的标记。
A mark left as a sign of passage of a person or animal.
某种品质的暗示
a suggestion of some quality
极少量,通常是残留的某种物质或材料。
A very small amount, often residual, of some substance or material.
印刷电路板上的导电路径。
A current-carrying conductive pathway on a printed circuit board.
干旱地区的非正式道路或显著路径。
An informal road or prominent path in an arid area.
马具上的两根带子、链条或绳索之一,从项圈或胸甲延伸到连接车辆或要拉的物体的横木；拉绳。
One of two straps, chains, or ropes of a harness, extending from the collar or breastplate to a whippletree attached to a vehicle or thing to be drawn; a tug.
连接杆或杆件,用于传递运动,尤其是从一个平面到另一个平面；特别是在风琴停止动作中用于传递运动的部件。
A connecting bar or rod, pivoted at each end to the end of another piece, for transmitting motion, especially from one plane to another; specifically, such a piece in an organ stop action to transmit motion from the trundle to the lever actuating the stop slider.
工程或建筑的平面图。
The ground plan of a work or works.
投影平面或原始平面与坐标平面的交线。
The intersection of a plane of projection, or an original plane, with a coordinate plane.
方阵对角线元素的总和。
The sum of the diagonal elements of a square matrix.
在句法结构中占据某个位置的空类别,用于解释如wh-移动和被动等结构。
An empty category occupying a position in the syntactic structure from which something has been moved, used to explain constructions such as wh-movement and the passive.
一系列指令,包括分支但不包括循环,针对某些输入数据执行。
A sequence of instructions, including branches but not loops, that is executed for some input data.
在缺乏稳定所指时的近似能指。
A signifier approximated in the absence of stable signified.
The test found a trace of lead in the drinking water.
检测发现饮用水中有微量的铅。
用法提示：trace 作名词，表示“微量、一丝”，此处强调极少量的存在。
AI contextual example
She spoke calmly, but there was a trace of nervousness in her voice.
她说得很平静，但声音里有一丝紧张。
用法提示：trace 作名词，表示“一丝、些许”，用于描述某种情感或特征的细微痕迹。
AI contextual example
After the rain, only a trace of the chalk drawing remained on the sidewalk.
雨后，人行道上只剩下粉笔画的一点点痕迹。
用法提示：trace 作名词，表示“痕迹、残留的少量”，指原来的东西所留下的少量残余。
AI contextual example
用 a trace of 表示极少的量或轻微的迹象，后接不可数名词或抽象名词。
There was a trace of sadness in her voice.
她的声音里有一丝伤感。
复数 traces 常指残留的痕迹、迹象，多用于具体物质或证据。
The police found traces of blood in the car.
警方在车里发现了血迹。
without a trace 是固定搭配，表示完全消失、不留任何痕迹。
The plane disappeared without a trace.
那架飞机消失得无影无踪。
track侧重连续留下的痕迹，如脚印或车辙
trail常指人或动物走过留下的痕迹序列，可能包括气味
footprint特指脚踩过的印痕
impression指物体按压留下的形状，强调压印
grammar · medium
易错句子There is trace of blood on the knife.
正确表达There is a trace of blood on the knife.
trace 在此表示“微量；一丝痕迹”，是可数名词；单数可数名词前必须有限定词（a/the/every 等），不能裸用。汉语“有……的痕迹”本身不带冠词，直译时就会漏掉 a，正确说法是 a trace of。
grammar · medium
易错句子The scientist found several trace of lead in the water.
正确表达The scientist found several traces of lead in the water.
trace 是可数名词，被 several 这类表示不定复数量的词修饰时，名词必须用复数形式 traces（词尾加 -s）。汉语名词不随数量变形，只靠数词表达，所以学习者容易保留单数 trace，漏掉 -s。
track 多指一长串可循的脚印、车辙或路线，常与 follow、picked up 等追踪动作连用；trace 侧重留下的痕迹本身，通常细微、零散，暗示原物已不在。
trail 常指人或动物经过后留下的一长串气味、足迹或线索，多用于追踪语境；trace 不强调连续的一串，而强调某物存在过的痕迹，往往需要仔细辨认。
mark 泛指任何看得见的记号或痕迹，可以是故意做上的；trace 特指某物存在或经过后无意留下的痕迹，常含“原物已消失”之意。
一丝…；微量…
There was a trace of sadness in her voice.
她的声音里有一丝悲伤。
留下痕迹
The thief left no trace behind.
小偷没有留下任何痕迹。
无影无踪地
He disappeared without a trace.
他消失得无影无踪。
微量元素
Zinc is a trace element essential for health.
锌是健康必需的微量元素。
微量证据
The lab found trace evidence of gunpowder on his hands.
实验室在他的手上发现了火药的微量证据。
痕量；微量
The water contains trace amounts of lead.
水中含有痕量的铅。
trace + -er
trace + -ing
trace + -able
trace + -ability
re- + trace
trace + element
痕迹常被视为证据的一种形式。
微量痕迹可成为破案线索。
脚印是常见的地面痕迹。
气味是难以察觉的痕迹。
痕迹可以表现为物体上的标记。
消失得无影无踪
The car vanished without a trace.
那辆车消失得无影无踪。
石沉大海；销声匿迹
Many small businesses sink without a trace during a recession.
许多小企业在经济衰退期间销声匿迹。
毫无痕迹；一点也没有
There was not a trace of sadness in her voice.
她的声音中毫无悲伤的痕迹。
Dictionary facts from DICTIONARY_API_DEV, ECDICT, WIKTIONARY, WORDNET.