This week she told me all about some trousers she's got for her holiday next week, and how they needed turning up (she's only wee, me mam). Then she told me she bought some invisible cotton to do it with. Never having heard of it, I thought she might be pulling my leg. Especially when she then said, "Have you ever tried threading a needle with invisible cotton? It's almost impossible...because you can't see the thread!!!". I thought that was the punchline and it really was a joke...but then she said "It took me 40 minutes! When I bought it on the market, I asked the woman if she had any invisible cotton, and she said did I want dark or light, and I said "What difference does it make if it's invisible?", and she said she didn't really know, so I got the light one. Maybe if I'd got the dark one I'd have been able to see it to thread the needle with!".
Now perhaps you begin to understand why I am the way I am...
Presumably if she'd bought the dark one and could see to thread the needle, she'd have been able to take it back and complain that it wasn't invisible? And how does she know she bought it if it's invisible?