He always sticks his nose into other people's business like a busybody.

He tried kumis for the first time.

He always buys cheap things, so in the end, it becomes 'penny wise and pound foolish'.

Acidic oxides react with water to produce acids.

Aluminum is an amphoteric oxide, it reacts with both acids and bases.

Peroxides play an important role in chemical reactions.

I will participate in an obstacle race this weekend.

In this situation, the proverb 'it is best to submit to circumstances' applies.

His long talk is just like 'a hundred days of sermonizing without a fart.'

In organic chemistry, pyruvic acid plays an important role.