However,occasionally even they are stumped, and when that happens they have to consult other experts, many of whom are found at the Smithsonian Museum of Natural History in Washington,D.C.

VOA: standard.2009.12.08

I found myself occasionally in disagreement with the direction that President Bush was headed, not very often, and not on any truly fundamental issues.

我偶尔会和布什总统,前进的方向存在分析，但不常有，而且不会,在一些基本问题上存在分歧。

普林斯顿公开课 - 国际座谈会课程节选