两道sat语法题,1.Arguing that every chemical element is composed o

两道sat语法题,
1.Arguing that every chemical element is composed of fundamental particles of a weight unique to that element,the English meteorologist JD presented the first modern atomic theory in 1803.既然有明显的过去时间词,为什么原句用“is”不用“was”?
2.In the book,LH recounts his childhood and early adulthood in language that is as simple and direct as another Missouri-born writer DC,one much admired by MT.
答案是“as another”,错在哪里了,是因为比较对象不平行而应该将其改为“as does another”吗?
另：the only one of the +复数名词+who ,后面谓语动词用单数还是复数?

1.Arguing that every chemical element is composed of fundamental particles of a weight unique to that element,the English meteorologist JD presented the first modern atomic theory in 1803.
分析如下——
用现在时态,chemical element is composed of fundamental particles 表示“化学成分是由基本粒子组成”这是一个亘古不变的事实；
用过去时态,chemical element was composed of fundamental particles 表示“化学成分曾经是由基本粒子组成”,意思指的是现在已经不是由基本粒子组成了；
因此,当表示一种真理的时候,不管相关谓语动词用的是什么时态,都需要用现在时表示.
2.In the book,LH recounts his childhood and early adulthood in language that is as simple and direct as another Missouri-born writer DC,one much admired by MT.
该题应该把 as another 改为 as of another 就成了平行结构.
解析：
因为比较主体 that（指代his childhood and early adulthood）指的是“时期”,
而比较对象：another Missouri-born writer DC,指的是“人”,
显然,“时期”和“人”不属于一个范畴,不能进行比较.
如果要比较,必须把比较对象变成 the childhood and early adulthood of another Missouri-born writer DC（密苏里州出生的作家DC的童年和成年早期）,同样也表示“时期”.
省略与上文重复的 the childhood and early adulthood,变成 of another Missouri-born writer DC.
这样,二者意思平行,就可以进行比较了.
关于 the only one of the +复数名词+who 的数的问题——
关系代词 who究竟指代的是单数名词还是复数名词,取决于先行词中的核心词.如果核心词是单数,谓语动词要用单数形式；如果核心词是复数,谓语动词要用复数形式.
后面谓语动词用单数还是复数?
“the only one of the +复数名词”中的核心词是 one,意思是“一些中唯一的一个”,既然是一个,就应该是单数,关系代词 who 指代单数名词 only one,因此应该用动词的单数形式.
如果改为“the two of the +复数名词”,核心词 two 是复数,这个短语就是复数概念,动词随之也应该用复数形式.