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they had lunch grouped by their military units. is the most popular phrase on the web.

they had lunch grouped into their military units 15,130,000 results on the web	they had lunch grouped by their military units. 1151,000,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
That's why they had lunch together every single week. Afterwards, they had lunch in a restaurant near the alpine center. My mom's not having dinner with George, they had lunch. So much so that the Romans incorporate those fighters into their military. The ex They had lunch yesterday in the regimental mess of the 1st Dragoon Guards. husband of some woman, said they had lunch at his place. Someone who had access to his food since they had lunch together every Sunday.	That's why they had lunch together every single week. Someone who had access to his food since they had lunch together every Sunday. Afterwards, they had lunch in a restaurant near the alpine center. They had lunch guests, but they all left. husband of some woman, said they had lunch at his place. The ex They had lunch yesterday in the regimental mess of the 1st Dragoon Guards. My mom's not having dinner with George, they had lunch.

they had lunch grouped into their military units

15,130,000 results on the web

they had lunch grouped by their military units.

1151,000,000 results on the web

More popular!

That's why they had lunch together every single week.
Afterwards, they had lunch in a restaurant near the alpine center.
My mom's not having dinner with George, they had lunch.
So much so that the Romans incorporate those fighters into their military.
The ex
They had lunch yesterday in the regimental mess of the 1st Dragoon Guards.
husband of some woman, said they had lunch at his place.
Someone who had access to his food since they had lunch together every Sunday.

That's why they had lunch together every single week.
Someone who had access to his food since they had lunch together every Sunday.
Afterwards, they had lunch in a restaurant near the alpine center.
They had lunch guests, but they all left.
husband of some woman, said they had lunch at his place.
The ex
They had lunch yesterday in the regimental mess of the 1st Dragoon Guards.
My mom's not having dinner with George, they had lunch.