"the preparatory stage" is a correct and usable part of a sentence in written English.
You can use it to refer to the period of time before something is implemented or the initial steps taken to prepare for something. For example, "We are currently in the preparatory stage of launching our new product."
For a couple of months now, journalists have been going along with the fiction that he isn't yet fully committed to the 2016 Presidential campaign, and is merely in the preparatory stage.
Ahimsa is one of the first disciplines learned by the student of Yoga and is required to be mastered in the preparatory stage (yama), the first of the eight stages that lead to perfect concentration.
Instruction is given at levels equivalent to those of the state schools, but in order to allow for greater emphasis on traditional Islamic subjects, the duration of training is lengthened by one year at the preparatory stage and two at the secondary.
In the preparatory stage of the solution process, this L-shaped element is subdivided into three smaller rectangular subdomains.
Two weeks after the regulations went into effect, the CBRC approved nine banks to enter the preparatory stage.
In the preparatory stage of product manufacturing, its defect risk is often evaluated by checking whether experimentally manufactured products cause the defect or not.
Bend It Like Beckham is in the preparatory stages, with Gurinder Chadha directing and writing, and Howard Goodall composing.
The authors find that that most of these deaths occur in attacks during the preparatory stages of the program.
As Dr Sarah Duncan, a space scientist involved with Aurora (the preparatory stages for manned missions to Mars), says, "Women have an important role to play because of their training in physics and space science".
Later in the preparatory stages, an SAS soldier quietly paid a call to the headquarters of the Royal School of Needlework, then a few doors along from the embassy, because their five-storey, 56-room building, with its huge pillared portico, had exactly the same layout inside and out as the embassy at No 16.
It's also worth noting that the preparatory stages of an IPO can last a couple of years, if not longer, and that Blue Apron could be merely dipping its toes in the water to see if it's warm.
