But the professor says it is difficult to find enough feathers from a single dinosaur to recreate all its colors.

VOA: special.2010.03.16

But it is difficult to read and judge a wave when it is near.

VOA: special.2009.03.17

Even today, it is difficult to walk or ride through the park.

VOA: special.2009.04.15

So it is difficult to see the animals in the sand.

VOA: special.2010.01.04

But it is difficult to put a price on troubled securities.

VOA: special.2009.01.30

It is difficult to tell exactly where the saying began.

VOA: special.2010.07.25

So when you talk to class four, he says,then it is difficult to teach the little kids in class one.

VOA: standard.2010.02.25

There is this audit and recount process. It is difficult to put a timeline to both of these activities at this point."

VOA: standard.2009.09.15

"I think one needs to recognize given the current state of relations it is difficult to describe it as a strategic one anymore.

VOA: standard.2009.10.27

He says it is difficult to know how the disease will evolve.

VOA: standard.2009.05.14

"Because there are only a couple of previous records of eruption at this particular volcano, it is difficult to judge either how long the activity will go on there, or how long the volcano might then be dormant before it goes active again."

VOA: standard.2010.04.15

However,this is more difficult because it is harder to control the diets of people and because they live longer than other animals.

VOA: special.2009.09.01

"It was not difficult to agree between us that neither party is in favor of handing any more powers to the European Union."

VOA: special.2010.05.14

Yet many people today cannot see the Maze District because it is so difficult to reach.

VOA: special.2009.04.15