The study aims to investigate the use of conjunctive adverbials (CA, hereafter) performing various textual relations in the English writing by Chinese speakers across genres and over time. To begin with, a corpus of one million word was compiled and the corpus interface was constructed. Later, 45 pieces of writing by 5 college students during 4 semesters were selected for data annotation and analysis, with each student contributing 9 pieces for 9 text genres. The results show that there exists a distribution norm of CA-performed textual relations based on CA occurrence frequency and that the distribution is independent of genre and time effects. Compared with literature, the found distribution is also considered free from the first language influence. This suggests that the found distribution is a mental representation of mature human cognition, underlying English writing on global and coherent levels. Therefore, the found distribution is of great potential for developing automatic tools of discourse diagnosis.