A major reason is that the dunes bury any plants in their way as they move across the desert.

VOA: special.2010.01.04

One reason is that overfishing of sharks and related fish has reduced the size of some shark populations.

VOA: special.2009.06.16

Another reason is that a small change in temperature can mean the difference between snow and rain.

VOA: special.2010.01.05

A major reason is prematurity the death rates are among the highest in the world.

VOA: special.2009.05.25

The main reason is the increase in the number of visitors to the islands.

VOA: special.2009.12.16

One reason is that heavy amounts of snow fall in surprisingly small areas.

VOA: special.2010.01.05

Nancy Drew expert Jennifer Fisher says the reason is no mystery.

VOA: special.2009.08.24

One reason is that it takes a long time;

VOA: special.2010.04.13

Another reason is concerns about environmental damage .

VOA: special.2010.10.08

College officials say one reason is low budgets.

VOA: special.2009.04.09

One reason is that there are more birds.

VOA: special.2009.04.01

One reason is the many national parks.

VOA: special.2009.04.15

The biggest reason is illiteracy.

VOA: special.2010.11.08

"The reason is that those plants are going to get so big that if you were to put three or four or six plants in, they are just going to be crowding each other out, and each plant is going to underperform."

VOA: special.2011.06.14