In story writing, interjections are used in dialogue to enhance the emotional tone of the text. However, crafting realistic dialogues that effectively incorporate interjections can be a challenging task for young learners with developing writing skills. This study examines how young learners utilize interjections in their story writing. The study analyzed the narratives of 242 students from three different English proficiency groups: lower and higher level EFL elementary school students and native English speakers in seventh to twelfth grade. The analysis aimed to understand the relationship between interjection frequency and writing qualities. The findings revealed a negative correlation between the occurrence of interjections and both content quality and vocabulary diversity. Additionally, comparisons across proficiency groups indicated that certain types of interjections were more prevalent in specific groups. These results suggest that learners should use interjections judiciously in story writing. Although interjections may seem peripheral, they warrant closer attention as they can subtly detract from writing qualities.

Traditionally, Centella asiatica leaf extracts are used to treat neurodegenerative diseases in India. Centella asiatica is reportedly used to enhance memory and treat dementia, but its promoting effect on neural stem cell differentiation has not been studied yet. In the present study, we investigated whether or not Centella asiatica leaf extracts act on neuronal precursor cells and neuronal cell lines to induce neuronal differentiation, neurite outgrowth, and neuroprotection. The neurogenesis-promoting potential of Centella asiatica leaf extracts was determined by differentiation assay on neural stem cells isolated from mouse embryos and PC12 cell lines. To understand the contribution of specific neural cell types towards increase after Centella asiatica treatment, neural stem cells were differentiated into various neural subtypes and checked by Western blotting using neural cell lineage-specific antibody markers. Neuroprotective activity of Centella asiatica was analyzed in PC12 cells exposed to 100 μM of H2O2. Cell growth was analyzed by MTT assay while cell death was analyzed by Western blotting detection of apoptosis-related proteins. Cells treated with Centella asiatica had significantly longer primary and secondary neurites as well as a higher number of neurites per cell compared to control cells. Expression levels of TUBBIII, TH, NF, and BDNF increased upon Centella asiatica treatment, suggesting that Centella asiatica has a neurogenesis-promoting effect. Centella asiatica also inhibited oxidative stress-induced neural cell damage through regulation of apoptosis- and cell cycle-related proteins. Thus, leaf extracts of Centella asiatica might promote neurogenesis, neuroregeneration, and neuroprotection in the context of neurodegenerative diseases.