Correct

绷脸

/ bēng liǎn / 
Strokes

Example

As a Verb

pull a long face; be sullen

1
Tā
他
běng
绷
zhe
着
liǎn
脸
  
,
yījùhuà
一句话
dōu
都
méi
没
shuō
说
  
。

With a long/straight face, he remained absolutely quiet.

2
Běng
绷
zhe
着
liǎn
脸

put on/pull/wear a long face