We report a boundary paradigm eye movement experiment to investigate whether the linguistic category of a two-character Chinese string affects how the second character of that string is processed in the parafovea during reading. We obtained clear preview effects in all conditions but, more importantly, found parafoveal-on-foveal effects whereby a nonsense preview of the second character influenced fixations on the first character. This effect occurred for monomorphemic words, but not for compound words or phrases. Also, in a word boundary demarcation experiment, we demonstrate that Chinese readers are not always consistent in their judgements of which characters in a sentence constitute words. We conclude that information regarding the combinatorial properties of characters in Chinese is used online to moderate the extent to which parafoveal characters are processed.