Hi, C.S. We were taught that words in an object clause should come in the declarative order. YES, THIS IS CORRECT. (Example: Tom saw Sarah running down the street.) And questions are usually in an interrogative order: Has she been here before? Why did he leave the room? HOWEVER When a question word clause is the object, we DON'T use the interrogative order. I don't know what does she want. (WRONG) I don't know what she wants. (RIGHT) I know how should it be spelled. (WRONG) I know how it should be spelled. (RIGHT) This confuses a lot of my students, because they see a question word and want to put the words in a question order. BUT NO QUESTION IS BEING ASKED, so we don't need the question order. ---------------------------------------- But I've come across sentences ( I cannot remember the exact words within) as below: ---- He asked her had she finished her embroidering. (THIS IS INCORRECT. It should be: "He asked her if she had finished her embroidering). ---- She didn't tell him why was she smiling that way. (THIS IS RIGHT, because it follows the rule for question word clauses being the object.

This is an advanced grammar topic. Embedded questions use the declarative order (as you stated). Indirect questions use the inverted order that you wondered about. Some dialects allow embedded questions with inverted order. Here is more information: https://ygdp.yale.edu/phenomena/inversion-embedded-questions