Word classes in Chinese have long been a controversial issue. There have been different opinions on this. Some linguists, e.g. Gao Mingkai, advocate the non-existence of word classes in Chinese. Others, e.g. Zhu Dexi and Lu Shuxiang, believe that there are word classes. Today, there is general agreement over the major word classes. There is however no general agreement as to whether the same word can belong to two or more classes. Some linguists recognise the possibility of 'a word being used temporarily as though it belongs to another word class'. But for most, 'dual class membership' is an exception.

Research on English has found 1300 examples of denominal verbs. The extent of overlapping in Cantonese, as revealed in this study, is far lesser than that in English. However, the phenomenon is by no means insignificant or uninteresting. A trend can be identified whereby more and more noun-verb overlapping can be expected in future.

Based on a 200,000-word database of spoken Cantonese and four Cantonese dictionaries, approximately 131 examples of monosyllabic words which show noun-verb overlapping have been found. The data shows that an overwhelmingly large part of noun-verb overlapping words in spoken Cantonese belong to the semantic category of 'instrument', though a not-too-small set belong to the category of 'shape'. On the other hand, disyllabic noun-verb overlapping data shows that more words belong to categories like 'work', 'product' and 'concept'. Traditionally, cases of word class overlapping are few in Chinese, but it is apparently on the increase in more recent times. The reasons may be convenience and speech fashion. These create room for word class overlapping.