Kind of and sort of of are often used in informal English (especially in American English) as adverbs, which act as attenuating words, meaning "somewhat\a little"; Take a look at the classic example sentences:
I like him, kind of.
I kind of like him.
I kind of like her.
I kind of like her.
This story is kind of boring.
The story is a bit boring.
I kind of like coffee.
I kind of like coffee.
I’m kind of tired.我有点儿累了。
They kind of laughed at me.
They kind of laughed at me.
The terrier was kind of short with long, black hair.
This one is a little short, with this long, black hair.
She also asked them if they would be too busy or kind of bored.
She also asked if they would be too busy or a little bored.
High School Entrance Examination Papers - 2016 Xinjiang
He was "kind of bored" and needed something to do.
He was "a bit bored" and needed to find something to do.
High School Entrance Examination Papers - 2016 Wuhan
It's kind of like only getting without giving, she explained.
It's a bit like getting something for nothing, she explains.
High School Entrance Examination Past Papers - 2018 Huanggang
When you give someone a tip, you’re sort of being polite.
When you stick your tongue out at someone, it's a bit rude.
As he was walking along, he sort of stumbled and seemed ill.
He walked forward, staggering, as if sick.
We were sort of worried about leaving Grandfather alone.
We were a little worried about leaving my grandfather alone.
He seems to have had some sort of religious experience.
He seems to have had some sort of religious experience.