An empirical study of claims and qualifiers in ESL students' argumentative writing based on Toulmin model

English argumentative writing is difficult in second language writing for ESL students. Although there has been a lot of research on English argumentative writings, empirical research focusing on claims in argumentative writing is very scarce. Based on the Toulmin model, this paper studied the relationship between the claims and English argumentative writing performance. 117 time-limited writings were collected at a top university in Northeast China. The qualifiers were in the form of words, participle and sentence (QW, QP, QS), based on which claims were classified. Through the text analysis of each argumentative writing, 23 types of claims were extracted. Types of claims and 117 argumentative writings were scored respectively. Correlation analysis showed that claims based on qualifier divisions did not predict holistic writing performance. Claims in the higher-mark writings were also discussed. The findings led us to conclude corresponding pedagogy implications in promoting argumentative writings.