vt.划线于；强调；提供伴奏乐

n.下划线；影片伴奏乐

Let me underscore two of many reasons for this concern. 值得担忧的原因很多，让我着重说明其中两点。

Please underscore the word three times for emphasis. 为了强调起见，请在该词下面划三条线。

Let me underscore that you should focus on an important problem. 让我强调一下：你必须关注于某一重要问题。

These results underscore the importance of context in studies of social capital. 这些结果强调了社会资本研究中环境的重要性。

They must begin with a letter or the underscore character 开始部分必须为一个字母或是下划线