It's difficult to understand the language of the Russians.

It's difficult to understand his explanation.

This problem is very difficult.

It's difficult to understand his explanation.

When I woke up early in the morning, there was dew on the grass.

His words always resonate in my heart.

He was a great assistance to my project.

His kindness is so great that it's unable to put into words.

His kindness is so great that it's unable to put into words.

Please help me, I got lost.