英语语法分析

Before 1815 manufacturing in the United States had been done in homes or shops by skilled artisans.

1815年以前，美国的产品制造是由熟练的工匠们在家里或商店里完成的。

The mosaics of Sepphoris were very likely created by traveling artisans from some other part of the Roman Empire.

Sepphoris 的马赛克很可能是由来自罗马帝国其他地方的旅行工匠创造的。

At first, thousands of unskilled laborers were recruited; by the 1730's, however, American employers demanded skilled artisans.

起初，数千名非熟练工人被招募；然而，到了18世纪30年代，美国的雇主需要有技术的工匠。