The ways that writers distinguish their opinions from facts and evaluate the certainty of their assertions is central to the meaning of academic texts, yet this is an area that second-language (L2) students often find extremely problematic. This paper examines the view that the items writers use to modify their claims, commonly referred to as hedges and boosters, may actually be unnoticed by L2 readers, a phenomenon G. Low (1996) called the lexical invisibility hypothesis. Data are presented from a small retrospective think-aloud study which explores how native Cantonese speakers (N = 14 undergraduates) respond to hedges and boosters in an academic text. The discussion is supported by questionnaire data which seek to determine learners’ awareness of the meanings of these forms. The results suggest that while the subjects generally attended to the boosters, hedges did seem to be more invisible.
