Scientists agree that musical instruments are a sign of fully modern behavior and a complex form of communication.

VOA: special.2009.08.18

Calculating building height was not a complex measurement in the late nineteenth century with early skyscrapers like the Home Insurance Building in Chicago.

VOA: special.2010.03.31

That sounds simple. But the issue is a complex mix of technical,business, political and legal questions.

VOA: special.2009.09.25

A navigator also had to know how to use a complex instrument called a sextant.

VOA: special.2009.12.23

Fugue is a series of opposing melodies used to create a complex effect.

VOA: special.2009.03.01

He was a complex individual with an often troubled private life.

VOA: special.2009.07.05

The James Webb Space Telescope is a complex engineering project.

VOA: special.2011.05.23

The awards were the result of a complex arbitration that was part of a peace agreement that ended the conflict.

VOA: standard.2009.08.20

Flavor aside, scientists have recognized it as a complex blend of chemical compounds with potential health effects, both good and bad.

VOA: standard.2010.06.30

Autism spectrum disorder is a complex neurological disorder that affects a person's ability to communicate and interact with others.

VOA: standard.2010.03.23

Transportation planning expert Alan Clark says traffic congestion is a complex problem whose solution calls for a comprehensive approach.

VOA: standard.2010.07.26

In a brief statement from the White House, Mr.Obama stressed this will be a complex and challenging operation.

VOA: standard.2010.01.13

Two recent public opinion polls offer a complex view of how Americans see the conflict in Afghanistan.

VOA: standard.2009.10.09

Malaria is caused by a complex parasite that makes it hard to target with a vaccine.

VOA: standard.2010.01.20