But connecting the dots between the ads and those activities has been difficult.
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It's been difficult getting exact numbers for children's allergies, and the new report isn't precise.
For non-premium content, it has been difficult to achieve sustainable profitability under these circumstances.
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The exact relationship between PEDs and interference has been difficult to pinpoint, A4A acknowledged.
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Shopping had always been difficult for her because of her constantly aching back.
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Journalism has always been difficult, and the arts have always been based on a patronage system.
Just a couple of years ago, that number would have been difficult to achieve.
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It could have been difficult for Romney to come out of his father's shadow.
Moving the needle at all has been difficult for retailers the last couple of years.
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This has been difficult to come to accept, but that is the truth of it.
As such, it's been difficult for outsiders to determine the size of the actual market.
It is has been difficult to prosecute cases of abuse in the ultra-Orthodox community.
It would have been difficult for him to have chosen two heirs apparent more like himself.
Alabama Gov. Robert Bentley said reaching a settlement that satisfies all states' competing interests has been difficult.
Telrite said it confirms Lifeline eligibility but said it had been difficult to verify the one-phone-per-household rule.
Mr Penny said that it would have been difficult to incorporate the signals into a homemade bomb.
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Cutting those fees has been difficult, since many investors are loth to part with familiar, time-tested benchmarks.
Many companies are reluctant or uninterested in discussing the issue, and concrete information has been difficult to obtain.
It's been difficult for magazine makers to create compelling digital editions that fit every screen size and resolution.
He said the sketches had been difficult to value, as Freud "destroyed so much of his early work".
In the United States it has always been difficult to prosecute publishers of financial opinions for securities fraud.
We have been trying to keep things in perspective, although that's been difficult as the big day approaches.
"These have been difficult weeks since the release of the grand jury report, " Cardinal Rigali said in a statement.
Her personal life has also clearly been difficult over the past few years.
Funding for protection of children in conflict zones has been difficult to secure.
Pietersen admitted the situation had been difficult, but insisted he was focused on regaining his place in the team.
We all know the past few years have been difficult for this country.
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At one time, being different may have been difficult -- for it wasn't just Princeton's crickets that startled Sotomayor.
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The road to this victory, Iowa, has been long, it has been difficult.
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It has been difficult to prosecute cases of abuse in the ultra-Orthodox community.
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