HSK 4 HSK V5
Correct

关键

/ guān jiàn  / 
Strokes

Collocation

1
关键性
2
关键时刻
3
非常关键
4
特别关键
5
抓关键
6
问题的关键

Definition

关键 is a Noun, which means [ hinge; key; crux; linchpin; lynchpin ].

关键 also is an Adjective, which means [ very important ].

Example

As an Adjective.
1
Zhè
这
cháng
场
bǐsài
比赛
hěn
很
guānjiàn
关键
  
。

This game is crucial.

2
Xiànzài
现在
dào
到
liǎo
了
bǐsài
比赛
de
的
guānjiàn
关键
shíkè
时刻
  
。

It's the crucial time of the race.

3
Tā
她
zài
在
guānjiàn
关键
shíkè
时刻
dǎduàn
打断
le
了
tánhuà
谈话
  
。

She interrupted the conversation at a critical moment.

As a Noun.
4
Qíshí
其实
rènhé
任何
shìqing
事情
dōu
都
bú
不
shi
是
juéduì
绝对
de
的
  
,
guānjiàn
关键
shì
是
háizi
孩子
zìjǐ
自己
de
的
nǔlì
努力
  
。

In fact, nothing is absolute, the key is the child's own efforts.