This and That

I am just starting Unit 13 and am having a little confusion over the words for “this” and “that.” If I wanted to write something such as, “This person . . .” while "that person . . . " would I write ὅδε for this and οὗτος for that? Or would I use ἐκεῖνος for that?

As a first approximation, ὅδε and οὗτος means “this”, the first for someone about to be mentioned, the latter for somebody already mentioned.
ἐκεῖνος means that

Coderch’s Greek Grammar available here http://coderch-greek-latin-grammar.weebly.com/uploads/1/1/8/5/11853710/greek_grammar.pdf is useful. See page 63 for examples. I would have copied and pasted all he says but the Greek is not properly encoded.

/ Difference οὗτος/ὅδε Both οὗτος and ὅδε mean THIS; nevertheless, οὗτος is used in reference to something which was already mentioned or is supposed to be already known by the reader:
To put it concisely: οὗτος “looks backwards” and ὅδε “looks forwards”.

Mastronarde is fairly clear here.

ὅδε, ἥδε, τόδε, this, referring to something very near, usually present or in sight



οὗτος, αὕτη, τοῦτο, this, the nearer. This word usually indicates something rela-tively close to the speaker, but not so close as something referred to by ὅδε



When used by itself, οὗτος most commonly refers backward, but occa-sionally it may refer forward. When contrasted with ἐκεῖνος, οὗτος means the latter versus the former. When contrasted with ὅδε, οὗτος refers backward (the foregoing vs. the following).

It takes a while to get your head round this.

So distance of time or space determines which word to use?

In Unit 13, Part III, exercise 5, I was supposed to write, “Those beloved children” in the accusative.
I wrote, “Ταῦτα τὰ φίλα παιδία.”

The answer book wrote, “ἐκεϊνα τὰ φίλα παιδία..”

I am unable to fine the line between Ταῦτα and ἐκεϊνα .

Would different authors have written different words for it?

those - ἐκεῖνα

these - ταῦτα