Sentence examples for difficult to be certain of from inspiring English sources

This makes it difficult to be certain of the actual number of species.

Given that there are going to be trade union demonstrations, it's difficult to be certain of the numbers of anti-Murdoch protesters expected to attend.

Because his donations are made through companies which he controls and not in his own name, it is difficult to be certain of their full extent.

But they caution that many dissidents are under constant harassment from their governments, so it is difficult to be certain of the cause of actions against them.

Rohmer guarded his private life fiercely – giving different versions of his date of birth and real name on ­different occasions, so that it is difficult to be certain of the truth.

"In working with our enormous vendor base, regularly buying items from hundreds of vendors, it is extremely difficult to be certain of the origin of each item, on each and every occasion," she said in an e-mail message.

Cavendish is indeed the author of Blazing World, but she also makes an appearance as a character, and it is difficult to be certain that all of the conclusions and insights of the narrator are ones that Cavendish would identify as her own.

It is difficult to be certain that all of the information recorded in each chart is completely accurate, especially if some was written retrospectively resulting in recall bias.

It is difficult to be certain what proportion of these decisions were discussed but not documented in the MDT care plan or how many were overlooked and the responsible clinician subsequently took a decision independently.

It is difficult to be certain about the concentrations of ions available to the haustoria of the parasite, as obtaining xylem sap (the presumed source) is in itself difficult.

Despite these reports, a systematic review which assessed interventions for educating traditional healers about sexually transmissible infections and HIV concluded that it was "difficult to be certain about the efficacy of interventions for educating traditional healers in the fundamentals of sexually transmissible infection and HIV medicine" [ 35].