Millie and I ____ in the Reading club. A.are all B.all are C.are both D.both are

Millie and I ____ in the Reading club. A.are all B.all are C.are both D.both are

应选C
首先Millie and I 是复数，这个应该知道的吧，故选项中肯定有be动词are，4个选项都有；
然后考察的是all与both的区别，all用于三者或三者以上，而both只用于两者，millie 与 I 是2个人，所以选用both，选项A 和B 排除；
最后呢，考察的是both位置的用法：
adj. 二者，两者都
pron. 二者
adv. 二者，二者都
conj. 不仅…而且…，…和…都
在此句中，both为形容词（adj.）be+形容词，构成系表结构 所以答案应为C
以下是both的一些例句可以看看参考一下：
1. He charged at me with his head down and both fists flying. 他低着头,挥舞双拳朝我冲来.
来自《简明英汉词典》
2. When we use " he " , we generalize for both sex. 当我们用 he 时, 我们泛指男女.
来自《简明英汉词典》
3. He held both sides of the parka hood closed against the snow. 他捏紧皮外套上风帽的两边以挡住袭来的飞雪.
来自《简明英汉词典》
4. The captain cares the safety of both the crew and the passengers. 船长为船员和旅客们的安全操心.
来自《简明英汉词典》
5. Bill is both a good swimmer and a good cook. 比尔不仅是个游泳好手,而且是个烹调能手.
来自《简明英汉词典》
6. Mental and physical deterioration both occur naturally with age. 随着年龄的增长,心智和体力自然衰退.
来自《简明英汉词典》
7. These habits are both universal among mankind and peculiar to individuals. 这些习惯在全人类中很普遍,而对个人来说又很独特.
来自《简明英汉词典》
8. Both the twin brothers were born and bred in London. 这对双胞胎兄弟是在伦敦长大的.
来自《简明英汉词典》
9. This is a ruler graduated in both inches and centimetres. 这是一把刻有英寸和厘米的尺子.
来自《简明英汉词典》