The phrase "and which expanded" is correct and usable in written English.
It can be used when referring to something that has been elaborated or made larger in scope or detail.
Example: "The project was initially small, and which expanded to include several new features over time."
Alternatives: "and that grew" or "and which developed".
With the war, his responsibilities broadened, as did the challenges of running a group whose stores suffered bomb damage, and which expanded in 1940 with the acquisition of struggling provincial stores.
Abu Anas is one of about two dozen defendants charged in federal court in Manhattan in a series of indictments that began in 1998, when Bin Laden was charged, and which expanded over the years to add other operatives.
She also spoke favorably of the Dodd-Frank overhaul of Wall Street, which President Obama signed in July and which expanded the Fed's mandate, and of proposed global bank regulations, known as Basel III, that will gradually force banks to hold more and higher-quality capital.
These include the highly successful implementation of the $5-a-day child care program in Quebec, the introduction of the Canada Child Tax Benefit in 1998 extending financial support to low income families with dependent children, and which expanded over the next decade, and the failed federal attempt to develop a national day care strategy in 2004.
The observed post-glacial expansion of Adélie penguins is common to many penguin species, including emperors [ 63], kings [ 64], gentoos and chinstraps [ 29], which all had populations smaller in size and restricted in range during the LGM, and which expanded post-glacially.
Which things would you like to change and which expand?
Her work traces that story to the police reform movements of the 1950s and 1960s, which expanded police training programs and lobbied for the recognition of officers as professionals, both inside and outside the courts.
Indeed, China's fastest-growing sector last year was wholesaling and retailing, which expanded at a double-digit rate.
The success of slick, grown-up shops including Cos and Whistles – which expanded in 2012 – shows a savvy, smart shopper had emerged.
Dr. Brazelton entered the public arena in 1969 with his book "Infants and Mothers," which expanded the concept of normal infant development.
The author wrote a paper with Miura and Takahasi which expanded the result of Hyers-Ulam stability of that differential equation.
