We use this expression to introduce a problem.
You can use this phrase in ………… language.
Spoken
Written
Informal
Example 1
A: Can you give me the report tomorrow?
B: Normally I’d love to. The thing is, I’ve got to be in Ostrava office all day today, so …
Example 2
A: Don’t you like milkshake?
B: Oh yes, I do. The thing is, I’m on a diet.