Sentence examples for have proved difficult at from inspiring English sources

Unlike Iran and the United States, it has cultivated ties with virtually every bloc in the country, though relations with Mr. Maliki have proved difficult at times.

Cannulation of the CS had proved difficult at the referring centre and although the implanter was able to place a 0.032in.

Demonstrating that transparency has proven difficult at times, however.

Málaga have proved difficult opponents for Barça recently at the Camp Nou, beating the champions 1-0 in February 2015 and losing only 1-0 laseasonseason

But weight loss campaigns have proved difficult.

Propulsion systems have proved difficult to shrink.

Additionally, some biopharmaceuticals such as antibodies have proven difficult to express at high levels.

In spite of the high heritability, the identification of genetic factors in ASDs has proved difficult, due at least in part to the fact that ASDs are characterized by a high degree of genetic heterogeneity.

To date, reference electrodes have proven difficult to miniaturize, hindering integration at the microscale.

Forest photosynthetic exchange rates at landscape scales have proven difficult to either accurately measure or estimate.

Reforms in that direction have proven difficult.