Sentence examples for posed a puzzle from inspiring English sources

The polygons of the dwarf planet Pluto have posed a puzzle for scientists.

For Dr. Kwon, Mr. Cartier's predicament posed a puzzle because he lacked some obvious signs of trouble; his implant, which was made by Stryker, had not been recalled, and the device had been implanted properly.

Over the last two months, a rash of destruction in Suffolk County -- fires set in newly built subdivisions, anti-meat graffiti, torched construction equipment -- posed a puzzle: Was it the work of a smart, devoted band of eco-terrorists or young vandals merely blowing off adolescent steam?

NGC 1275, located 235 million light-years from Earth near the center of a clump of galaxies known as the Perseus cluster, has posed a puzzle: How have these filaments, which are made of gas much cooler than the surrounding intergalactic cloud, persisted for perhaps 100 million years?

But an area beneath French Polynesia posed a puzzle: Why was that swath of ocean thousands of miles from a plate boundary so shallow and its floor riddled with volcanoes?

The condition has posed a puzzle for researchers because they assumed the blood-brain barrier, a protective system that excludes most pathogens and immune molecules from the brain, would block signals from the immune system.

This poses a puzzle.

Which poses a puzzle.

Infectious cancer poses a puzzle for biologists.

All this poses a puzzle for conventional economics.

Nonetheless, the emergence of OSS poses a puzzle for conceptions of organisational theory.