For a French person living in Perth the word 'esky' is unknown and discussing 'thongs' can land you in a tricky situation.

That was what it was like for PhD candidate Sophie Richard when she arrived in Perth on exchange.

A trip to the supermarket where the checkout woman asked her "Owsyadaybin?", left her wondering "Who's Debbie?".

Ms Richard said she had to get the woman to repeat her sentence several times before she could understand the question she was being asked.

She had learnt English in her home country of France and spent time in both the UK and the US.

"I thought I could speak English by that time, but I guess not," she said.

The experience prompted her to try to ascertain whether Perth has its own peculiar way of using English.

Previous studies have focused on the sounds of the language, but Ms Richard's study at the University of Western Australia will look at grammar.

Perth's grammar under the microscope

"The specific thing that I look at is the form of words, so basically when you tell a story, are you going to put an 'ed' at the end and say 'I worked', or are you going to use the present or are you going to use a different tense," she said.

Over the next five months she hopes to interview 120 Perth men and women of different ages and from different socio-economic backgrounds.

"I look at those stories and I will extract all the verbs in those stories and the form they use, and then there's a lot of statistical analysis to figure out who does what," she explained.

"Language doesn't exist by itself without the speakers, the people using the language."

Ms Richard is a bit secretive about the actual phrase or speech pattern she is focusing on.

"If I tell you what I'm looking for, the people I interview will be thinking about it and I don't want that," she said.

The speech pattern she has identified was not just isolated in Western Australia.

"What's interesting with this feature is that it has been seen in the UK, but not in the US," she said.

She added it could be distilled down to when people left the UK for the US.

"When the language was transplanted it was in a different stage," she said.

"This is a snapshot of language at the moment, it's about how language changes and evolves."

Anyone who wants to be a part of the study should contact the University of Western Australia.