Sentence examples for a puzzling problem from inspiring English sources

America faces a puzzling problem, he mused in his speech.

The set pressure in pressure relief valves (PRVs) varying with the type of sealed medium has been a puzzling problem in the field of chemical machinery and equipment for many years.

In God's benevolent design, carnivores caused mercifully swift death, but the suffering caused by parasitism was a puzzling problem.

Human languages evolve continuously, and a puzzling problem is how to reconcile the apparent robustness of most of the deep linguistic structures we use with the evidence that they undergo possibly slow, yet ceaseless, changes.

The location of the NL-binding site in the membrane-proximal LNS6 domain of α-Nrx had been a puzzling problem due to the fact that the large (∼1,100 residues) membrane-distal segment must be accommodated in the narrow space of the synaptic cleft (∼20 nm).

This belief implied a puzzling problem because specific CD8+ T cell responses appear to be strongly associated with different viral set-point levels in patients [3], [37], but the death rate of virus-producing cells is very similar in different patients [14].

But he was left with "a really puzzling problem," Mitrovica said.

The assembly of subunits into complex I has proved to be a very puzzling problem to address, complicated by the size of the enzyme and its dual genomic control.

Even though he did a best-selling memoir about his roots, he has had a persistent and puzzling problem coming across as rooted.

Electron or ion irradiation-induced phase change between the amorphous and crystalline state is a long-standing and puzzling problem.

This work aims to solve the puzzling problem by offering a combined approach and evaluating how important on earth the PL conversion could be in improving solar cell efficiency.