The phrase "make extensive efforts" is correct and can be used in written English.
You can use it to describe specific actions that require a lot of effort to complete. For example: "The company has made extensive efforts to reduce their carbon footprint."
We make extensive efforts to adjust analyses for the risk of the patients.
Gov. Bob Taft (R) is highly unpopular thanks to the poor economy and tax increases under his watch, and the Bush-Cheney campaign will make extensive efforts to boost the president's image there on its own.
We make extensive efforts to ride the waves of every trend, ensuring every article of clothing we select is acceptable and "in".
Therefore, systematic reviews might locate all available trials (even if unpublished) and make extensive efforts to include them, similar to the efforts typically made to reduce loss to follow-up in clinical trials.
Mr. Fager said CBS had made extensive efforts to determine what Mr. Davies told the F.B.I.
Amy Brundage, a White House spokeswoman, said the Obama administration had made extensive efforts to alert taxpayers to the new credits.
"We've made extensive efforts to try to find him," said Joshua White, the deputy city attorney trying the case.
But even on that subject, Professor Moglen said, Judge Jackson made extensive efforts to portray his approach as consistent with the law.
The Royal Thai Government has been making extensive efforts at home and in cooperation with other countries to address the narcotics problem faced by Thailand.
He said his team had made extensive efforts to contact the witnesses on Mr. Milosevic's list and had managed to persuade very few to attend.
Merkel and Hollande have made extensive efforts to resolve Ukraine's 16-month pro-Russia uprising and return peace to the EU's turbulent eastern front.
