To better understand Chinese English learners'processing of input materials during the continuation task,this study explores noticing in input processing,with topic familiarity as the task variable.It examines learners'input processing in two stages:before writing and during writing.The study integrates think-aloud protocols,notes,and retrospective interview data to analyze noticing from three dimensions:meaning,form,and organization.It is found that:1)Before writing,noticing of meaning accounts for the highest proportion,while during writing,noticing of form is the most prominent;2)Topic familiarity does not affect noticing distribution before writing.However,during the rereading stage of writing,tasks with high topic familiarity trigger a higher proportion of noticing related to meaning,whereas tasks with low topic familiarity trigger a higher proportion of noticing related to form.