How can the native English speakers tell that a speaker is not a native speaker but a learner once they hear the learner speak?

这项研究的目的是调查母语为英语的人在听到一个学习者说话后，是如何分辨出说话者不是母语者，而是学习者的。特别强调的是搭配表达。我比较了英语学习者使用的搭配表达和母语人士使用的搭配表达，并分析了母语对搭配表达的影响。我创建了一个特殊的平行语料库，其中包括英语学习者的句子，英语母语者的句子和日语翻译。定量比较表明，以英语为母语的人比以外语为母语的人多使用1.2个搭配表达。利用语料库对语境中的搭配表达进行定性比较，证明了这种比较方法可以使学习者的表达追求外来语的“听性”成为可能。利用本研究建立的方法，我们可以对英语学习者使用的搭配表达进行系统的研究。虽然本研究中部分语料库数据是手工处理的，但公式化数据的处理可以通过计算机编程实现自动化，这将提高调查的效率。

The purpose of this research is to investigate how native English speakers can tell that a speaker is not a native speaker but a learner once they hear the learner speak. Special emphasis has been placed on collocational expressions. I have compared the collocational expressions that EFL learners use to those which only native English speakers use, and analyzed the influence of the EFL learners' mother tongue.I have created a special parallel corpus which consists of EFL learners' sentences, native English speakers' sentences, and the Japanese translation. The quantitative comparison shows that the native English speakers use about 1.2 more collocational expressions than EFL learners. The qualitative comparison of the collocational expressions within the context using the corpus has proved that this method of comparison makes it possible to pursue the foreign "soundingness" of EFL learners' expressions.With the method which has been established in this research, we can conduct systematic studies on collocational expressions that EFL learners use. Although some of the corpus data has been manually processed in this research, formulaic data processing can be automated by computer programming, which will make the investigation more efficient.