A. "Can someone explain to me how do I know when to use this instead of that?" B. "Can someone explain to me how I know when to use this instead of that?"
Hi, A. "Can someone explain to me how do I know when to use this instead of that?" Not OK.
B. "Can someone explain to me how I know when to use this instead of that?" OK.
As a direct question "how do I know when to use this instead of that?" is correct. But it's not correct to use this direct question word order in sentence A, because the direct q