The phrase "already arranged with" is correct and usable in written English.
You can use it when indicating that a prior agreement or arrangement has been made with someone.
Example: "The meeting is already arranged with the client for next Tuesday at 10 AM."
Alternatives: "previously coordinated with" or "already set up with".
Aircell has already arranged partnerships with American Airlines and Virgin America and plans to install its equipment on an American 767-200 this month.
Wanting to take his genetics into a multicellular organism, he'd already arranged a postdoc with developmental neurobiologist Edward Hedgecock, who studies C. elegans at Johns Hopkins University in Baltimore.
Something like "I'm sorry, I already arranged a meeting with a friend.
"We are going to Abu Dhabi, racing and talking to potential buyers with meetings already arranged out there," he said.
This would allow the Easters to surrender at an appointed time, with bail already arranged, and they could be in and out of booking quickly.
Jacob Berte, 20, who is transferring to Iowa from Iowa Central Community College, in Fort Dodge, said he had already arranged to live in an apartment with two friends from high school.
AIG has plans to spin these subsidiaries into private companies and has already arranged a debt-for-equity swap with the New York Fed.
A number of countries, Japan among them, have already arranged to replace Chinese-sourced REMs with that of other countries, such as Vietnam, Mongolia, Kazakhstan, Greenland, and India.
Plotting the average across units of this index, which reflects the decrease of the variance in the angles between triplets, already observed in Figure 6, we see again, that after roughly 4 million time steps the system is already arranged in a stable ordered manner, with equilateral triangles among neighboring fields that dominate the activity pattern.
