或A或B, A这A那, 左A右B: more four-character moulds
【六25】【六27】【六28】四字格 / fixed patterns
Tone colorsā tone 1á tone 2ǎ tone 3à tone 4a neutral
Three four-character moulds whose slots you fill yourself, unlike a fixed 成语. 或A或B: "be it A or B", two options, most often opposites (或大或小, 或喜或悲). A这A那: you repeat the verb to say "this and that", often with a reproach or an endless list (说这说那, 问这问那, 嫌这嫌那). 左A右B: you repeat the same or a neighbouring verb "in every direction", for insistence (左思右想, 左看右看, 左躲右闪).
They join the moulds of the 四字格 page (不A不B, 半A半B, 东A西B, 无A无B…). 这 and 那 do not point at real things: they mean "all sorts of things", and 左 and 右 are not real directions.
Examples
这些书或厚或薄，我都想看。
Zhèxiē shū huò hòu huò báo, wǒ dōu xiǎng kàn.These books, thick or thin, I want to read them all.
孩子们或坐或站，都在认真地听故事。
Háizimen huò zuò huò zhàn, dōu zài rènzhēn de tīng gùshi.Some seated, some standing, the children were all listening to the story intently.
妈妈问这问那，其实是关心我。
Māma wèn zhè wèn nà, qíshí shì guānxīn wǒ.Mum asks this and that, but really she is showing she cares.
他挑这挑那，最后什么也没买。
Tā tiāo zhè tiāo nà, zuìhòu shénme yě méi mǎi.He picked at this and that and in the end bought nothing.
我左思右想，还是决定告诉她真相。
Wǒ zuǒ sī yòu xiǎng, háishi juédìng gàosu tā zhēnxiàng.After turning it over and over in my mind, I still decided to tell her the truth.
他在人群里左看右看，却没有找到那张熟悉的脸。
Tā zài rénqún lǐ zuǒ kàn yòu kàn, què méiyǒu zhǎodào nà zhāng shúxi de liǎn.He looked this way and that in the crowd but did not find the familiar face.
Common mistakes
✗ 说这那 → ✓ 说这说那 (the verb is repeated on both sides).
✗ 左想右看 → ✓ 左思右想 / 左看右看 (A and B are the same verb or two very close ones).
✗ 或高和矮 → ✓ 或高或矮 (the mould repeats 或, with no 和 in between).