The words “Caesar” and “dais” are not exactly everyday words, but when they do appear in stories or news items, they are often misspelled.
The problem with Caesar is that the English pronunciation is /see zer/ so the English speaker wants to put the “e” directly after the “C.” I learned how to spell it when I took high school Latin. I liked writing the AE as a digraph (two letters written as one). My Latin teacher didn’t mind, but my English teacher hated it. Indeed, my love of the joined AE influenced my adoption of the name “Maeve.”
The error with dais is to reverse the vowels. I first encountered dais in stories about King Arthur. At every feast, Arthur and Guinevere were “seated on a daïs.”
English doesn’t generally make use of accents, but with a few words, like dais, the diaeresis (two dots over the letter), is an aid to pronunciation since it tells the reader that the second vowel begins a new syllable:
daïs, a platform raised usually above the floor of a hall or large room to give distinction or prominence to those occupying it
coëval, of the same or equal age or antiquity
naïve, marked by simplicity
Boëthius, author of Consolation of Philosophy
Charlotte Brontë, author of Jane Eyre
Zoë, popular female name from Greek, meaning “life giving”
Bettë Davis (1908-1989), liberated woman who created a new kind of screen heroine.