"Illegal logging is such a big problem simply because of the size of it.

VOA: standard.2010.07.28

I started thinking, you know what, the reason why in the United States we have such a problem,

你知道我开始想什么了吗，我在想为什么在美国我们会出现如此的问题，

发挥创造力的瞬间 - SpeakingMax英语口语达人

Today,the number is still 40 percent. Part of the problem is that a number of big importers, such as China and Japan, are not doing enough to stop the import and sale of illegal timber.

VOA: standard.2010.07.28