TOEFL Reading: ETS-TOEFL阅读机经 - 2ZGH4BNCPEO_R0TNL$

According to paragraph 5, which of the following was true of the process of bringing new land under cultivation A. It began in interior areas and quickly spread to areas near water. B. It was completed near the end of the eighteenth century. C. It occurred slowly because most uncultivated land was not very fertile. D. It often occurred as a result of farming families working longer hours.