The phrase "a large and complicated" is correct and usable in written English.
You can use it to describe something that is both significant in size and complex in nature.
Example: "The project we are undertaking is a large and complicated endeavor that will require extensive planning and resources."
Alternatives: "a big and complex" or "a substantial and intricate".
This was a large and complicated bill.
In real life, however, product development is a large and complicated process.
That was his notion of how to run such a large and complicated business.
Physicists say such setbacks are an inevitable part of starting up such a large and complicated machine, which has cost $8 billion and taken 14 years.
"Childhood is a time when one is presented with the pieces of a large and complicated jigsaw puzzle," Alice later observes.
George Tzimopoulos, a Manhattan real estate lawyer, said that most buyers willingly hired lawyers because they recognize that they need legal guidance for such a large and complicated purchase.
But he also stressed that the Catholic Church's World Youth Day, which brought an estimated 3 million people onto Copacabana beach Sunday after a week of activities, was an especially large and complicated event, a claim echoed by Gilberto Carvalho, a senior aide to President Dilma Rousseff.
Therefore, we ended up with a very large and complicated law that people do not understand or trust, and happiness with our health care system has been pushed further down the road.
Making a product as large and complicated as a trailer is no small feat, as Wiltshire learned.
"Today, it's a corporate structure, large and complicated place".
"The peace process is a comprehensive and large and complicated set of issues," Mr. Grossman, the United States' special representative for Afghanistan and Pakistan, said in a news conference here on Sunday after meeting with President Hamid Karzai of Afghanistan.
