He always used to say, 'It's easy to say, but hard to do.'

He is good at expressing his feelings well.

In order to find the inverse function, you need to solve the original function's equation for x and y.

I was really impressed by his piano performance.

We cannot proceed with this project because vital information is missing.

Please find the derivative of this function.

His health condition is my biggest concern.

I am enjoying viewing paintings at the art museum.

In physics, the inertial frame of reference is a very important concept.

I want him to stop interfering with my work.