Artificial flowers are used for
scientific as Well as for decorative purposes. They are made from{{U}} (51)
{{/U}}of materials, such as wax and glass, so skillfully that they can
scarcely be{{U}} (52) {{/U}}from natural flowers. In making such models,
painstaking skill and artistry are called for,{{U}} (53) {{/U}}thorough
knowledge of plant structure. The{{U}} (54) {{/U}}of glass flowers in
the Botanical Museum of Harvard University is the most famous in North America
and is widely known{{U}} (55) {{/U}}the scientific world{{U}}. (56)
{{/U}}, there are several thousand models in colored glass, the work of two
artist naturalists, Leopold Blalschka and his son Rudolph. The
intention was to have the collection{{U}} (57) {{/U}}at least one member
of each flower family native to the United States.{{U}} (58) {{/U}}it
was never completed, it contains more than seven hundred species representing
164 families of flowering plants.{{U}} (59) {{/U}}detail of these is
accurately reproduced in color and structure. The models are{{U}} (60)
{{/U}}n locked cases as they are too valuable and fragile for classroom
use.
【正确答案】
A
【答案解析】B项some和D项several均表示“一些”，some/several of后面应当接表示限定范围的名词或代词，如：some of the students，several of them。因此，用在本句不合适。C项a sort表示“一种”，这与句子后半部分的举例相矛盾，因而也不能适用。正确答案应选A项a variety，表示“种种”。
【正确答案】
B
【答案解析】本题要求填入一个能与介词from搭配的及物动词，A项compared“比较”和C项 contrasted“对比”后接介词with或to，故不符合句子结构的要求。D项differed后接from，但它是不及物动词，没有被动语态。正确答案为B项distinguished“区别”，distinguish A from B意为“把A与B区别开来”。
【正确答案】
C
【答案解析】从句子结构看，本题要求填入—个连接名词短语的连接词或词组，四个选项中，A项in addition“而且”和D项moreover“此外”都为副词，不能连接两个并列的成分。B项as well“也”必须与as连用，由于句子中前半部分的and连接的是painstaking skill和artistry，并不是与as well连用，故不能选B。正确答案为C，as well as相当于and。