Hints and tips:
...The students also found that Schlumberger, the world’s largest oilfield services company, gave the university an unknown amount of money....
...It is unknown if Mr Koszary will have any oversight of Mr Musk’s social media output....
...Mr Lawani and Mr Soyoye, both in their early 40s, boast the kind of résumés that can lure wary investors into what is still perceived by many as unknown territory....
...Murders are unknown in the corrupt but genteel world of cricket, and that improbability made Woolmer’s story entrancing....
International Edition