Topic-Comment sentences (TCSs) have been shown to be common structures in many languages. However, they are one of the most controversial linguistic issues and thus pose challenges for a lot of language learners. With the purpose to examine the features of TCSs in Vietnamese and English, the purpose of this study is to improve understanding of these structures in both English teaching and learning as well as Vietnamese. The ultimate purpose of this research is to assist learners of the two languages in avoiding negative transfers and making better use of TCSs in translation and in everyday communication by offering a comparative examination of the structures in English and Vietnamese