"Can you tell me where is the bank?" or "where the bank is." [duplicate]

Can you tell me which of the following sentences is grammatical?

"Could you tell me where the bank is, please?" "Could you tell me where is the bank, please?"

And please, explain why. Thank you in advance.

"Could you tell me where is the bank, please?"

is an Untag construction. (I've just made up this theory, so don't take it as authoritative.) It's from

"Where is the bank, could you tell me please?"

by a mysterious process that restores the tag to the complement structure that the speaker imagines it must have been derived from. Except he forgot to uninvert the "is" auxiliary, which is a telltale sign that the "where" was really supposed to come at the beginning of the sentence.

It's similar to an example reported by Jerry Morgen,

I think the Yankees lost the pennant, didn't they?

where the tag shows us that the sentence really starts with "The Yankees ...", and the "I think" has just been stuck on as an afterthought.

The second one is not strictly grammatical, for the reason that it repeats the interrogation of the sentence.

I can say Where is the bank? or Could you tell me where the bank is, please?.

Both of those are questions. But if I say Could you tell me where is the bank, I am placing a double interrogation, in the forms of Could you and where is. So it tends to sound awkward in English.

Having said that, it is a mistake that non-native speakers frequently make. I have particularly noticed it in the speech of other Europeans. Because it is a small error, and everyone understands you, people will not normally correct you. That may be one reason why the mistake persists.

English (normal, non-pidgin English) is a language with a strong DIE-DRY (Duplication is evil - don't repeat yourself) principle.

• Do you know {<statement> | <statement fragment>} ?
• Do you know {where the house is} ?

• Do you know if {she did ask "where is the house?" } ?
• Do you know if {she asked "where is the house?" } ?

• Do you know <direct question> ?
• Do you know {where is the house?} ?
• Do you know if {did she ask "where is the house?" ? } ?