Correct

虽 vs 虽然 vs 虽说

/ suī vs suīrán vs suīshuō /
Strokes

Definition

虽, 虽然 and 虽说 are all Conjunctions, which means “though; although”.

Example

虽, 虽然, and 虽说 mean "although" (in spite of the fact)to show concession, and the clause that follows usually takes 可是, 但是, 却 in correspondence to the main clause.
虽 is more literary, 虽说 is more colloquial, and 虽然 is general. 虽 is usually used after the subject, whereas the other two can be used either before or after the subject:

In the above examples, 虽 cannot be used in examples ④ ⑥, yet the three words are interchangeable in examples ① ② ③ ⑤.
1
suī
不大
tóng
同意
  
,
shì
可是
gǎn
míngshuō
明说
chūlái
出来
  

He dare not express that he only partly agree.

2
Tiān
天气
suī
zhuǎi
nuǎn
  
,
zǎowǎn
早晚
hái
jiào
比较
liáng
  

It becomes warmer,but it's still cold in the mornings and at nights.

3
Zhè
háizi
孩子
suīrán
虽然
xiǎo
  
,
dàn
què
hěn
dǒngshì
懂事
  

Young as he is,the child is very sensible.

4
Suīrán
虽然
děi
shēngyīn
声音
gāo
  
,
dàn
zài
yuǎnchù
远处
néng
tīngjiàn
听见
  

Although his voice was not high, he could be heard from a distance.

5
Zhè
fu
衣服
suīshuō
虽说
tài
piàoliang
漂亮
  
,
shì
可是
bǎonuǎn
保暖
xìngnéng
性能
hěn
hǎo
  

Although this dress is not very beautiful, it has good warmth performance.

6
Suīshuō
虽说
xīnnián
新年
kuài
dào
liǎo
  
,
què
méiyǒu
没有
diǎn
guònián
过年
de
xīnqíng
心情
  

Although the New Year is coming, he is not in the mood of it.

Sometimes when 虽然 etc. are used in the second clause to introduce, it functions as a supplementary explanation.
7
Zhàngfu
丈夫
xiàn
发现
妻子
de
xìng
性格
yǒuxiē
有些
yàng
一样
suīrán
虽然
  
(
suī
  
)
  
(
suīshuō
虽说
  
)
zhǐshì
只是
xiē
一些
wēi
细微
de
biànhuà
变化
  

The husband notices that his wife's personality is somewhat different, although it is only a slight change.

8
Zhāng
lǎobǎn
老板
de
shēng
生意
jīnnián
今年
zhuànqián
赚钱
le
  
,
suīrán
虽然
  
(
suī
  
)
  
(
suīshuō
虽说
  
)
zhuàn
de
tài
duō
  

Mr. Zhang made money in his business through he made only a little.