unsolved

The problem still unsolved, he turned to the work which had brought him to the office.

Eventually she had to get off the phone, with the problem unsolved.

Some of these problems are unsolved to this day; others were soon made clear.

In any case, the problem of cost control would remain unsolved.

With everything unsolved - up in the air - no answer to our question.

Dark matter is one of the significant unsolved problems in modern science.

She was never found and the case remained unsolved as of 2008.

However, there is no real evidence, so the crime goes unsolved.

The call could come at any time, and a key problem remained unsolved.

She has not been found and the case remains unsolved to this day.

The four color problem remained unsolved for more than a century.

But the study said medical inflation was still an unsolved problem.

Season four is about a mystery, left unsolved for 30 years.

To this day, his cause of death still remains unsolved.

But he knows from experience that almost all such cases remain unsolved.

There may even be an unsolved murder on the books from years past.

She was one of those people who will not leave a mystery unsolved.

Each one always has a set of unsolved problems demanding my attention.

That a major case goes unsolved is not unusual here.

Those unsolved murders were a part of me now, too.

This was a game that remained unsolved for many months.

So are the unsolved ones and the latest hot research areas.

Her murder would remain unsolved for the next 40 years.

However the case still has been considered an unsolved mystery.

More than three years after the murders, the case was still unsolved.