46.Implicit in it is an aesthetic principle as well：that the medium has certain qualities of beauty
and expressiveness with which sculptors must bring their own aesthetic sensibilities into
harmony.
(倒装结构 Implicit in it is an aesthetic principle as well=An aesthetic principle is implicit in it as
well，that 引导的句子做 principle 的同位语)
其中也蕴涵一个美学原则：用于雕刻的媒介物有一定的美和富于表现力的特性，雕刻家必须
使他们自己的审美感与这些特性融为和谐的—体。
分句 1：Implicit in it is…
分句 2：that the medium has…
分句 3：which sculptors must bring…
3 和 2 嵌套
1 和 2 嵌套
47.With the turn-of-century Crafts movement and the discovery of nontraditional sources of
inspiration，such as wooden African figures and masks，there arose a new urge for hands-on,
personal execution of art and an interaction with the medium.
(there arose…是一个存在句)
随着世纪之交的手工艺运动和非传统灵感源泉(像非洲形体和面具)的发现，出现了一种亲自
实践、亲手制作艺术和与媒介物直接接触的新要求。
本句为单句，with 引导并列的两个短语作为伴随状态，真正的主语为 a new surge
48.The common kestrel roosts and hunts alone，but the lesser kestrel roosts and hunts in flocks，
possibly so one bird can learn from others where to find insect swarms.
(possibly so=possibly so that)
普通红隼单独栖息和狩猎，但较小的红隼群栖群食，很可能因此一只鸟可以从其他鸟那儿了
解到在哪儿可以找到成群的昆虫。
分句 1：the common kestrel…
分句 2：but
分句 3：possibly so…
分句 4：where to…
1，2 和 3 并列
3 和 4 嵌套