Correct

叽叽嘎嘎

/ jī jī gāgā /
Strokes

Definition

(onom.) giggling noise

Example

As an Onomatope

[used for sound of chatting and laughing shrilly] cackle

1
zài
lǎoshī
老师
shēnhòu
身后
zuò
guǐliǎn
鬼脸
shí
  
,
bān
shàng
suǒyǒu
所有
de
xuésheng
学生
dōu
叽叽嘎嘎
de
xiào
le
lai
起来
  

When he made faces at the teacher's back, all the students in the classroom started cackling.

As an Onomatope

[used for sound made by a bed or a badly-oiled door, etc] creak; crackle

2
tǎngxià
躺下
  
,
chuáng
jiù
叽叽嘎嘎
de
xiǎng
  

The bed creaked as he lay down on it.

3
Zhè
mén
zǒngshì
总是
叽叽嘎嘎
de
xiǎng
  

The door is always creaking.