5. Washoe could make signs to communicate
6. Some scientists doubted
7. Washoe taught three younger chimps sign language
8. The experimenters thought Washoe was intelligent
A if the Gardeners argument was sound
B because she was cleverer than other chimps
C when she wanted to eat
D while she was at a research center in Ellensburg
E because she could use sign language to ask for fruits
F while Washoe was learning sign language
答案与题解：
1. C 第一段主要介绍猩猩Washoe的出生地、死亡年龄、被带到美国学习美式手语等一般情况。用General Information about Washoe来概括是很准确的。
2. B 第二段的关键句是In 1969， the Gardners described Washoes progress in a scientific report.随后的句子简略的介绍了Washoe的学习情况和结果，如已学会了250个单词，并能用手语表达“该吃饭了”等概念。所以，Report about Washoes Progress in Learning Sign Language(选项B)是答案。
3. E 第三段介绍了对Gardener夫妇发表的报告有两种不同的解读。一派认为Washoe的手语能力只是机械重复、死记硬背、物质激励的结果，不是智能的表现。另一派认为知识智能的表现，其证据是Washoe还能教三个小猩猩学习手语。争论的焦点是猩猩有没有智能。选项E用debate来概括上述争论，所以是答案。
4. A 第四段解释了为什么现在从事这项研究的科学家人数不多。部分原因是研究周期太长。
5. C 选C 的第四段第二句：Washoe made signs to communicate when it was time to eat.
6. A 第三段的上半段说了一些科学家对Gardener 夫妇的试验的解读所持怀疑态度。题干中出现的doubted引导我们选A.
7. D 选D DE 依据是第三段的最后一句，即“He took Washoe to a research center in Ellensburg， Washington. There， Washoe taught sign language to three younger chimpanzees， which are still alive.”
8. E 本文第二段谈到试验的成果时有一个句子：“She could request foods like apples and bananas”。根据全段意思和上述句子，选择E是正确的。