unknown in a sentence

Any complications those women experienced remain unknown .

Fields where ownership is unknown are left blank.

The bilingual brain is still very unknown .

The true story remained unknown until 1928.

These non union directors are unknown independent directors.

It is still unknown whether bone recovers completely.

The actual crop damage estimate was unknown .

Such grand vistas must harbor unknown secrets.

What percentage has a placebo effect is unknown .

Of course surface tension was an unknown phenomenon.

It remains unknown why this name was chosen.

His total number of victims is unknown .

The exact purpose of each program is unknown .

The exact causes of migraine headaches are unknown .

Unemployment money and social security help was practically unknown .

Even the real population size is unknown .

And entirely unknown myself until this week.

The identities of those killed are unknown .