Do you understand the concept of the time value of money? ✬

I really like the concept of this website. ✬

Tom struggles with this concept. ✬

Tom is struggling with this concept. ✬

What a concept! ✬

I assume you're familiar with this concept. ✬

That's hardly a new concept. ✬

Do you understand the concept? ✬

The concept is amazing. ✬

The concept has changed. ✬