医生们仍然无法确定出了什么问题。

The doctors are still unable to ___determine what is wrong.

你可以用一个简单的测试来确定油漆是否含铅。

You can use a simple test to ___determine whether the paint contains lead.

我们对此问题的感受促使我们班在福特汉姆当地居民中开展了一项调查，以统计确定后者使用格林代尔公园的频率。

Our feelings about the issue led our class to direct a survey among local residents in Fordham, in order to ___determine statistically how often the latter use Greendale Park.