Cows need about two to four weeks to learn to use the robotic milking systems.

VOA: special.2009.05.12

Planting beans every two to four weeks until early August will provide a continuous harvest.

VOA: special.2009.03.24

By the thirty-fourth week, it could remember the sound for four weeks.

VOA: special.2010.11.30

While the adults go out at night for food, the young bats hang out in the cave for four or five weeks.

VOA: special.2009.12.07

Later,she takes the soap out of the mold and places it in a storage area to cure or dry for four to six weeks.

VOA: special.2011.03.09

"Those are the babies who are born between thirty-four and thirty-seven weeks gestation.

VOA: special.2009.10.26

Two weeks later, four more would-be bombers tried, but failed to attack underground trains.

VOA: standard.2010.04.01

Those tests,we anticipate, will take approximately four to six additional weeks."

VOA: standard.2009.06.26

You got four full weeks of vacation - twice the usual paid time away - and editors got a week of company-paid educational travel to anyplace they wanted to go in the country.

VOA: standard.2010.03.08

Analyst Ali Nourizadeh, of the London-based Center for Arab and Iranian Studies, says the Iranian government is doing its best to prevent students from protesting, but he thinks student determination to go ahead with Monday's rallies is stronger: "The regime has already started four,five weeks ago arresting students.

VOA: standard.2009.12.07

General Myers spent four years as the top U.S.military officer, starting just weeks after the September 11 attacks in 2001, through the early successes in Afghanistan and Iraq and the beginning of the Iraqi insurgency, and ending in late 2005, just before the major outbreak of violence in Iraq and well before the resurgence of the Taliban in Afghanistan during the last two years.

VOA: standard.2009.10.16