Tourism is a major source of income for the area.

旅游业是这个地区的主要收入来源。

《牛津词典》

Fish was a major source of protein for the working man.

鱼曾是劳动者获取蛋白质的主要来源。

《柯林斯英汉双解大词典》

The sun is the major source of energy for our planet.

太阳是我们星球能量的主要来源。

youdao

The Ogallala aquifer is a major source of drinking and irrigation water for America's central plains.

VOA: special.2011.07.08

For a typical household, the home is the major source of wealth that they've accumulated.

对于一个典型的家庭来说,他们积累的财富主要就是住宅

耶鲁公开课 - 金融市场课程节选

The plant is a major source of food energy and a major food security crop.

VOA: special.2010.06.08

The oil and gas sector currently represents a major source of economic growth and jobs.

FORBES: The Jobs Speech Obama Should Give, But Won't

Dr. TILMAN: Corn is a major source of food for the U.S. and the world.

NPR: Biofuels and Food Prices

Power says that baggage fees continue to be a major source of passenger dissatisfaction.

FORBES: America's Most Satisfying Airlines