This study aims to examine functional idiosyncrasies of seemingly synonymous constructions and explain their frequency distributions in different spoken registers. To this end, lexical and discoursal approaches in the corpus-based research of constructions are combined to investigate how significant collocates of three suggesting constructions – namely, let's, what/how about and why don't you/we – are contextually situated in British English. Constructional analyses of the spoken part of the British National Corpus show that the three suggesting constructions primarily perform different metadiscourse and directive functions. Based on these functional variations, the present study explains the distribution and usage of the three suggesting constructions across the five spoken registers.
