I fully agree with his opinion.

I fully approve of his opinion.

Stock prices change every day.

It's dangerous to fall off the boat without wearing a life jacket.

He decided to accompany on the trip.

I accompanied her to the party.

He always lives without forgetting a child's mind.

North Korea has launched another ballistic missile.

My favorite fairy tale is Cinderella.

'Agreement' and 'synonym' sound similar, but their meanings are completely different.