Sentence examples similar to achieving it has been difficult from inspiring English sources

Although attempts have been made to achieve this (Maachi and Jones 1997), it has been difficult to reach and agreement on this issue.

It has been difficult to achieve on smartphones because of hardware limitations.

It has been difficult to achieve similar door-to-balloon times for transfer patients in the United States.

In many communities in the United States it has been difficult to achieve high rates of breastfeeding initiation.

An alternative approach is to use live attenuated RSV; however, it has been difficult to achieve the appropriate level of attenuation for infants.

In practice, it has been difficult to achieve good ethanol yields above WIS contents of around 10% (cf. Tables 2 and 3).

Although a number of vectors can transfer genes to synovium quite effectively, it has been difficult to achieve long-term transgene expression in the joints of experimental animals.

At the same time, it has been difficult to simultaneously achieve high conversion efficiencies and long-term operating stability, given that the semiconductors offering the highest efficiencies are susceptible to corrosion during cell operation.

It has been difficult for Washington to achieve more, since, noted SIGAR, "security and political goals consistently trumped strong anticorruption actions". Moreover, U.S. aid has exacerbated the problem.

However, achieving recruitment goals has been difficult for researchers.

However, achieving this relationship has been difficult for established luxury and fashion brands.