great grandparent

"My adopt-a-grandparent friends are very nice, have great stories and are very wise" , she says.

“我收养一个祖父母朋友都很漂亮，而且非常英明伟大的故事”，她说。

For maintenance of the good traits of practical varieties, five different methods for succession of great grandparent silkworm were applied and compared.

为了有效保持生产实用家蚕品种的优良性状，在家蚕母种继代繁育中采用5种选择方法选择继代蛾区，探讨种性维持效果。

Over much of the globe, the living standard of, say, a farmer in 1750 would not differ greatly from that of his great-grandparent.

例如，在全世界大多数地区，一个农民在1750年的生活水平和他的曾祖辈没有太大区别。

Effect of Selection Method for Succession of Great Grandparent Silkworm on Maintenance of Characteristics

家蚕母种继代蛾区选择方法对种性维持的影响