·       track [træk]， trace[treɪs]

·         Trace: 去发现，查考，找到，描摹，追溯
i.e. The book TRACES the development of philosophy. 该书追溯了哲学的发展过程。

Track:去跟踪，追踪
i.e. The hunter TRACKED the wolf and managed to catch it. 猎人追踪狼，并设法逮住它。

Both of them can be used as nouns.
When trace is as noun, it means a mark, an object or a sign that shows that somebody/something existed or was present.
When track is as noun, it means a path or road, or rails that a train moves along, as well as part of a tape or computer disk that music or information can be recorded on, soundtrack, for example.

·          ---------------------------------------------------

Trace n.

1. 痕迹;遗迹

The archaeologists found some traces of an ancient civilization in that area.考古学家们在那个地区发现了一些古代文明的遗迹。

2. 丝毫,微量There was barely a trace of salt in the soup.汤里简直一点盐也没有放。

He always spoke with a trace of sarcasm.他说话总带着一丝讽刺。

3. (记录仪器上存留的)图形,记录

vt.

1. 跟踪;追踪[(+to)]The police traced the criminal.警察追踪罪犯。

2. 查出,探出The post office tried to trace the lost letter.邮局设法查出那封丢失的信。

3. 追溯;查考[(+back/to)]The book traces the development of philosophy.该书追溯了哲学的发展过程。

4. 描绘;勾出...的轮廓[(+out)]

5. (费力,细心地)写(字)

6. 描摹,摹写;复写The kids are learning to trace the letter.孩子们学描字母。

vi.

1. 沿着路走

2. 上溯[(+to)]His fear of snakes traces back to an experience in his childhood.他对蛇的惧怕溯自他孩童时的一次经历。

trace  n.    1. 挽绳,缰绳kick over the traces摆脱控制;不顺

track

1. 行踪;轨道;足迹

We followed his tracks in the snow to a hut.我们沿着他在雪地上留下的足迹走到一间小屋旁。

2. 小径,小道

3. 铁轨,轨道The train jumped the track.火车出轨了。

4. 【体】跑道;径赛运动He runs around the track every morning.他每天清晨绕着跑道跑步。

5. 历程;行动路线;思路You're on the wrong track.你想得不对了。

6. 惯例,常规

7. (坦克等的)履带

vt.

1. 跟踪;追踪[(+to)]

It was not long before I tracked down the lost wallet.不久我就找到了遗失的钱包。

The hunter tracked the wolf and managed to catch it.猎人追踪狼,并设法逮住它。

2. 沿着(道路)走

3. 走过,通过

4. 在...上留下足迹

The dog tracked mud all over the shiny kitchen.狗在厨房发亮的地板上留下一屋子泥。

The child rushed into the room and tracked dirt over the floor.小孩冲进房间,地板上全是带泥的脚印。

5. 为...铺轨

vi.

1. 追踪

2. 留下足迹

3. (摄影机)跟踪摄影[Q]

4. 走[(+about)]

Trail  vt.

1. 拖,曳

2. 跟踪;追猎

[(+to)]The police trailed the thief.警察跟踪小偷。

3. 落后于

4. 拖带The boy trailed a toy horse after him.男孩将一匹玩具马拖在身后。

5. 在...上踩出路;标出(路)

6. 预告(节目)

vi.

1.       拖在或跟在(...的后面)[(+along/behind)]

The children trailed behind their teacher.孩子们跟在老师后面走。

2. 拖沓行走

3. 拖曳;垂下The young girl’s hair trailed over her shoulder.年轻姑娘的长发披肩。

4. (杂草等)蔓生[Q]There is ivy trailing all over the wall.常春藤蔓生整个墙面。

5. 追踪猎物

6. 减弱;变小[(+off/away)]

n.

1. 痕迹;踪迹;足迹The hounds found the trail of the fox.猎犬发现了狐狸的踪迹。

2. (荒野中踏成的)小道3. 一缕;一长串;一系列[(+of)]

They made a trail of protests against the decision.他们对该项决定提出了一连串抗议。

4. 拖曳物,尾部;拖裾;蔓

The wagon left a trail of dust.大篷车过处扬起一团灰尘