Correct

没脑子

/ méi nǎo zi /
Strokes
https://i.cchatty2.com/filters:format(webp)/fit-in/684x0/img/202102/没脑子-Chinese-idioms-Cchatty-9886fbdd-bb26-4e57-a3cb-5bdc8ca14a55-1612777608.jpg

Collocation

1
没脑子的人
2
没一点儿脑子
3
骂/说……没脑子
4
总是没脑子

Definition

没脑子

Literally means:

brainless

Actually means:

thoughtless

It figuratively means that somebody lacks the ability to think and reason. It is often used to mean that somebody is careless and thoughtless when talking about something or doing something. Derogatory

比喻缺乏思考、推理等方面的能力。常指说话、做事不动脑筋,不认真思考。有贬义色彩。

Example

Used as predicate or attributive, and can be used with other words in between. (作谓语、定语,中间可以插入别的词语)
1
yǒu
nǎozi
脑子
  
,
kěn
yònggōng
用功
  
,
guǎn
不管
xué
shénme
什么
  
,
dōu
xué
de
hěnkuài
很快
  
;
yòu
lǎn
yòu
méi
nǎozi
脑子
  
,
zěnme
怎么
de
shàng
ne
  
?

He has a brain, he is willing to work hard, no matter what he learns, he learns very fast;

2
zěnme
怎么
zhème
这么
méi
nǎozi
脑子
  
,
fēn
qīng
shuí
duì
shuí
cuò
  

Why are you so brainless that you can't tell who's right and who's wrong.

3
yào
不要
shēng
生气
  
,
jiùshì
就是
zhèzhǒng
这种
méi
nǎozi
脑子
de
rén
  
,
zhīdào
知道
shénme
什么
huà
gāi
shuō
  
,
shénme
什么
huà
gāi
shuō
  

You don't want to be angry with him, he's such a brainless person who doesn't know what to say and what not to say.