How can an alien word in an explanatory book be written, in italics or to capitalize the first letter?
I refer here to both types of alien words; one which is mentioned only one time in a book and that mentioned repeatedly.
alien = foreign
Yes, Kitty, foreign words are usually typed in italics, whether they're used once or repeatedly throughout the text. As regards capitals, use them as you would normally use them in ordinary text, i.e. for proper nouns, etc.
-Not a teacher-