彼は極端に偏った考え方をする人だの英語

His way of thinking is a bit extreme.

He holds extreme views in politics.

He's laboring under a grave misapprehension.

He keeps a lot of thoughts inside.

He is possessed with a curious notion―obsessed by a strange notion.

He's sadly lacking in common sense.

I feel his idea stupid.

He sticks to his own opinion.

He is absolutely wanting in common sense.

He holds moderate views―temperate views.

She gives a precise opinion under a well put together judgment.

He has the very opposite opinion.

His way of thinking is sound.

He is in the habit of talking in a roundabout manner.

His idea lacks originality.

He has a strange habit.

He holds extreme views―radical views―ultra views.

He has a habit of tilting his head to one side.

He is embarrassed in manner.

His opinion carries weight.

He persists in his opinion.

His idea is persuasive.

he is outright dishonest

he has a proclivity for exaggeration

He has peculiar ways.

He is sadly mistaken.

He has the vice of lying.

his illiberally biased way of thinking

I positively say my opinions.

With all his ignorance, he sets up for a critic.