Beesley of Mid-continent Research for Education and Learning in Denver.
丹佛中州教育和学习研究组织的安德里亚。德。比斯利说道。
2
Of the 20 countries that were endemic in the mid 1980s, only 4 (all on the African continent) are still reporting cases.
上世纪80年代中期曾经流行该病的20个国家中，仅有4个国家(全部在非洲大陆)仍然报告发生病例。
3
The formation of the continent, mid-range, fine three-in-one source system, its large quantity and variety of complete, effectively protects the surrounding areas of the capital and consumer demand.