"is undergoing improvement" is grammatically correct and can be used in written English.
It is typically used to describe something that is currently being improved or upgraded. For example: - The company's customer service system is currently undergoing improvement to provide better support to their clients. - The city's public transportation network is undergoing improvement to make it more efficient and accessible for commuters. - The school's curriculum is constantly undergoing improvement to meet the changing needs of students.
Currently, they represent situations of unsustainability in cities worldwide that are undergoing improvement.
The mobile site may be undergoing improvement to correct the problem stated above.
This beam line is undergoing constant improvement.
"I think the biggest impact of the light rail is less tangible," said Matt Pool, owner of Matt's Big Breakfast, a busy spot along the line, "which is that it really improves the image and perception of Phoenix's downtown, which, although experiencing a significant renaissance in recent years, still is undergoing many improvements and changes.
However, in order to make the method robust and applicable for commercial field use, the specialised testing and processing device is undergoing refinement and improvement.
QMy building in Manhattan is being converted to a condominium and is undergoing some major improvements, including a new lobby and new windows, radiators, electrical system and air-conditioners and sleeves.
This picture is likely to be found in any secondary school in the country that is undergoing substantial attempts at improvement.
The country's infrastructure is undergoing massive expansion and improvement: Roads are being widened, treacherous switchbacks are getting guardrails, and freshly dug tunnels are cutting travel times by an hour or more.
Proton, too, is undergoing a series of improvements, including a widening of its fairing, says ILS president Phil Slack.
The field of structural biology is undergoing dramatic changes as improvements in technology—such as the development of free-electron lasers and improved detectors for electron microscopy are making it possible to solve structures at atomic resolution, almost in a high-throughput manner.
