Tell me please which sentence is correct.
I wonder what they are doing.
I wonder what are they doing?
Tell me please which sentence is correct.
I wonder what they are doing.
I wonder what are they doing?
I wonder what they are doing.
See Questions and negatives | LearnEnglish - British Council:
We sometimes use phrases like these in front of a statement to ask questions:
Do you know …? I wonder … Can you tell me …?
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For wh-questions, we use the phrases with a question word:
Do you know who lives here?
I wonder how much this dress is.
Can you tell me where she comes from?
We often use do you think …? after question words:
How much do you think this dress is?
Where do you think she comes from?
Who do you think lives here?