A dying woman covered in burns did not answer a police officer who repeatedly asked "who did this to you, was it your husband?", a Sydney jury has been told.

Neighbour Paul Ciantar said Parwinder Kaur just looked at the officer, turned her head to the side and didn't say anything as she lay on the footpath outside her Rouse Hill home.

Kulwinder Singh leaves the Supreme Court in Sydney. Credit:AAP

She told an officer "please cover me up" as a blanket was held up to give her privacy when her smouldering underpants were gently cut away from her body.

Mr Ciantar was giving evidence on Friday in the NSW Supreme Court at the trial of Kulwinder Singh, 41, who has pleaded not guilty to murdering his 32-year-old wife in December 2013.