But professors at big schools say there is not enough time to write evaluations for each student in large classes.

VOA: special.2009.03.05

These kind of natural and spontaneous arrangements are not global, they're not big enough and important enough.

这种自发性的商议,并不是全球性的，它们的规模不够大，也不那么重要。

耶鲁公开课 - 金融市场课程节选

The Obama administration has been especially attuned to criticism that it is not doing enough for small business, and focusing too much on helping big corporations and financial firms.

VOA: standard.2009.03.16

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