How can I add a new level to a multilevel ordered list on the same line as the parent item?

I am trying to write a question paper in Cambridge O Level question format.

I saw this kind of list:

1. Main list Item 12. Main list Item 2    (a) Sub list item 1  (b) Sub list item 2  (c) (i)  Sub Sub list item 1      (ii) Sub Sub list item 2

As shown here, imbedded list (c) and imbedded imbedded list (i) are on the same line, list (c) doesn't have any text in it.

I have searched the internet and the only solutions I've found require inserting a table.

Does anyone know a way to make a list behave this way in Google Sheets?