Is this correct : "Make sentences and write them (or "these") down." ?
♥♦♣♠ NOT A TEACHER ♥♦♣♠ Make sentences and write them down. - them = the sentences made by you Make sentences and write these down. - these = some other sentences or words you are asked to write down, not the sentences you make
I think the first sentence, as it stands, is clear to you. As for the other, these cannot mean them - these must be referring to something already created and present in writing, something that someone may be showing and asking you to write down - it could be anything in plural.