Correct

一丝

/ yī sī /
Strokes

Example

As a Measure word

a tiny bit; a trace

1
yōushāng
忧伤

a trace of sadness

2
xīn
疑心

a touch of suspicion

3
yángguāng
阳光

a thread of sunlight

4
xiàoróng
笑容

a trace of a smile

5
wàng
希望

a gleam of hope

6
wēixiào
微笑

a wisp/ghost of a smile; a faint smile

7
huái
怀疑

a flicker of doubt

8
fēng

a breath of wind

9
cháofěng
嘲讽

a touch of derision

10
àohuǐ
懊悔
  
/
妒忌

a faint twinge of remorse/jealousy