The milk froze and became solid. ✬

This house has a solid foundation. ✬

Water becomes solid when it freezes. ✬

The water in the basin has frozen solid. ✬

Ice is solid. ✬

Columns provide a solid foundation. ✬

Tom hasn't been able to eat solid food since his accident. ✬

Today, for the first time in a week, Tom was able to eat solid food. ✬

It was a solid gold bar. ✬

All of the suspects have solid alibis. ✬