老师建议对这篇论文进行一些删减以使其更简洁。

The teacher recommended some ___deletions to make the essay more concise.

基因检测显示他的染色体上有一处缺失。

The genetic test revealed a small ___deletion on his chromosome.

定期备份可以防止重要文件被意外删除。

Regular backups can prevent accidental ___deletions of important files.