"It would be difficult to keep that under wraps".
"But this will be difficult to keep alive.
Still, it can be difficult to keep the reins tight in cyberspace, even for Mr. Springsteen.
He said it would be difficult to keep the jersey all the way to Paris.
In terms of pitching, the great performances are not exactly unexpected, even if they will be difficult to keep up.
When you have a lot of energy, as I do, it can be difficult to keep things under control.
However, without taking the nonchemical steps outlined above, it will be difficult to keep these pests out of the building.
Privately, American officials suggested that if progress was not made by Monday, it would be difficult to keep going.
A hard-core group of regulars fill many of the slots, and beginners are welcome, though it can be difficult to keep up.
It can be difficult to keep things moving quickly enough, and yet to keep alive the sense that what is happening is unfolding gradually.
It's clear that in the city that never sleeps, it can be difficult to keep up with road repairs at the rate problems spring up.
