Marton man Richard James Parkinson is on trial in the High Court in Palmerston North, charged with raping four children.

A woman says she was plied with alcohol, choked and had duct tape put over her mouth before a man raped her when she was a child.

But the defendant's lawyer says some of the rapes described were physically impossible to perform due to the accused's "big beer gut".

Richard James Parkinson is on trial in the High Court in Palmerston North, charged with raping two girls and two boys in the Rangitīkei town of Marton in the 2000s.

He is also charged with assault with an airgun, threatening to kill and supplying alcohol to minors. He has pleaded not guilty to all charges.

READ MORE: Marton man on trial for sexually abusing children after giving them alcohol

The first of the four complainants started giving evidence on Friday, after her evidential interview was played to court on Thursday.

In her interview, she said Parkinson gave her raspberry vodka RTDs before the attacks.

The first incident involved the pair being in a swimming pool with another young girl.

The two girls were running around the pool when Parkinson, sitting in the corner of the pool, grabbed and raped them one after the other, the complainant said.

She described various other rapes, including a time when he put duct tape over her mouth to stop her screaming for help.

She also said she was once given so much alcohol she blacked out, waking up on a bed under a blanket naked and sore.

He would often given her money he got from a safe in a cupboard afterwards, she said.

Defence lawyer Peter Brosnahan suggested various parts of the complainant's story had changed between her evidential interview and her testimony in court.

That included the order he allegedly raped the girls in while in the pool and the colour of a blanket she said was on the bed.

She said she did get some things wrong in her interview, but denied allegations the rapes did not happen.

Brosnahan also put to her the pool rapes could not happen, as she had described Parkinson sitting down with his legs slightly bent in front of him.

Parkinson's "big beer gut" would have got in the way of any rape, Brosnahan said.

"I'm suggesting to you it is an impossible scenario to achieve."

Furthermore, the drinks had been Golden Circle fizzy drinks, and being grabbed in the pool was a "game" not involving rape, Brosnahan said.

The complainant said that was wrong.

The trial before Justice Helen Cull alone continues.