A corpus-based study of English synonyms: appropriate, proper, and suitable

The sources of data used in this study are 1) three dictionaries, i.e. Longman Dictionary of Contemporary English 6th edition (2014), Longman Advanced American Dictionary 3rd edition (2013), and Macmillan Collocations Dictionary (2010), and 2) the Corpus of Contemporary American English (COCA).

It was discovered that the three synonyms share the same core meaning, but still differ in terms of detailed meanings, degrees of formality, collocations, and grammatical patterns. For this reason, the three words cannot be used interchangeably in all contexts. In addition, it was found that the corpus provides some data which is non-existent in the three dictionaries.