Describes the cause and action for error messages.
Error Message(English)：
can not merge and center
Merge and Center Not Available (Microsoft Excel) - Excel Tips - Tips.Net
https://excel.tips.net/T005398_Merge_and_Center_Not_Available.html
How to enable merge and center in excel 2010 - YouTube
https://www.youtube.com/watch?v=pfPh-_8EwjQ
https://www.youtube.com/watch?v=pfPh-_8EwjQ
how to enable merge and center button in excel - YouTube
https://www.youtube.com/watch?v=7KGYlHa85YQ
https://www.youtube.com/watch?v=7KGYlHa85YQ
Merge and unmerge cells - Office Support
https://support.office.com/en-us/article/merge-and-unmerge-cells-5cbd15d5-9375-4540-907f-c673a93fced・・・
How to merge cells in a range formatted as table in Excel? - ExtendOffice
https://www.extendoffice.com/documents/excel/4488-excel-merge-cells-in-table.html
Excel - How to Merge Cells - University of Wisconsin KnowledgeBase
https://kb.wisc.edu/page.php?id=939
Stop merging cells! - Access Analytic
https://accessanalytic.com.au/stop-merging-cells/