Sentence examples for proved difficult to maintain from inspiring English sources

Neutrality proved difficult to maintain, though.

But this distinction has proved difficult to maintain.

By 1849 however, it proved difficult to maintain the old system and in that year the metric system became the legal system of measure in Spain.

Further complicating things, parts for the theatre's Edison and Simplex projectors were difficult to come by at the best of times, and the complex machines proved difficult to maintain.

The toxic dinoflagellate Gambierdiscus has also proved difficult to maintain in culture; it grows slowly and does not attain high biomass [ 66- 68].

With regard to the goa-1, egl-30 double mutant, as found by other researchers before us [ 16], these double-mutant animals proved difficult to maintain, became extremely sick and were impossible to be assayed reliably for avoidance.

But that success may prove difficult to maintain, depending in large part on decisions the Texas Legislature will make this year to confront a budget shortfall that could reach $20 billion or more.

Consequently, it has proven difficult to maintain surfactant-producing cells [9].

But design runs a lot deeper and, with the growing portfolio of products, Google's philosophy of keeping it simple with minimalism is proving difficult to maintain.

However, the captive population was small and not viable for long-term breeding, and captive sifakas have proven difficult to maintain due to their specialized dietary needs.

That sort of restraint, however, could prove difficult to maintain in New York, where Sanders will be under constant attack from Clinton, her surrogates and even the state's famously feisty news media.