借人气问一道 RC题目-----感谢请教。

Dendrochronology, the study of
tree-ring records to glean information about the past, is possible because each
year a tree adds a new layer of wood between the existing wood and the
bark.  In temperate and subpolar
climates, cells added at the growing season's start are large and thin-walled,
but later the new cells that develop are smaller and thick-walled; the growing
season is followed by a period of dormancy. 
When a tree trunk is viewed in cross section, a boundary line is
normally visible between the small-celled wood added at the end of the growing
season in the previous year and the large-celled spring wood of the following
year's growing season.  The annual growth
pattern appears as a series of larger and larger rings.  In wet years rings are broad; during drought
years they are narrow, since the trees grow less.  Often, ring patterns of dead trees of
different, but overlapping, ages can be correlated to provide an extended index
of past climate conditions.

However, trees that grew in areas
with a steady supply of groundwater show little variation in ring width from
year to year; these "complacent" rings tell nothing about changes in
climate.  And trees in extremely dry
regions may go a year or two without adding any rings, thereby introducing uncertainties into the
count.  Certain species  sometimes add more than one ring in a single
year, when growth halts temporarily and then starts again.

Question #50.  341-02  (23608-!-item-!-188;#058&000341-02)

The passage suggests which of the
following about the ring patterns of two trees that grew in the same area and
that were of different, but overlapping, ages?

(A) The rings corresponding to the
overlapping years would often exhibit similar patterns.

(B) The rings corresponding to the
years in which only one of the trees was alive would not reliably indicate the
climate conditions of those years.

(C) The rings corresponding to the
overlapping years would exhibit similar patterns only if the trees were of the
same species.

(D) The rings corresponding to the
overlapping years could not be complacent rings.

(E) The rings corresponding to the
overlapping years would provide a more reliable index of dry climate conditions
than of wet conditions.

请问A是怎么得出的呢？这里overlapping year是同一年的意思吗？

最后一段末尾 说 trees of certain species 一年里会长出 more than one ring, 如果这样，凭什么说 任意的两颗  树在同一年一定会show similar pattern。

Certain trees一年长 两道 年轮，Other trees 一年长 一道年轮，它们怎么会 show similar pattern?

个人感觉这是一道考TF的题，第一段是中心，第二段是辅，而且用的是WOULD，最符合作者的表达，没有那么绝对。ETS考点中一般不喜欢把句子完全重复，而是改几个词。

第一段就是说树轮是可以显示当时的天气情况的。

第二段只是列了几个个别的特别的地方，一个是有地下水的，一个是特别干旱的地方，才会产生UNCERTAIN的情况。但是也没有否定TF.

我自己也是最近才摸索出了一点方法，就是把自己做错的选项分析，看看当时为何我产生这样的想法，当然理解文章是主要的。如果一篇文章就3道题目全错，不是你想法的问题，或者仔细不仔细的问题而是你完全没有读懂，如果只是错了个别的细节题，那就是ETS的TRICKY题。就是关于混，无，绝对这些分析就会派到作用。个人感觉，自己也在复习中。。互相学习一下吧。

我觉得楼主你这题，要不是文章没有读懂，要不就是整个逻辑意思还没搞清楚。因为你给出的2段，第二段只是用来rule out最后一个选项，并且E是一个明显的“反”项。你如果着眼第二段，应该是找不到正确答案的。

第一段介绍了年轮产生的机制，以及这个年轮概念的运用。     第一段后面2句就是把年轮机制推广一下，说明在同一个地区环境下，不同的年龄的树，可能因为共同经历了一些年份，会因此显示出年轮模式上的相似性。

用句土话来说，假如   一个树1000年历史，活到2009年，另外一棵树，200年历史，活到2007年。 但是我们知道在1950年－－－－1960年间是10年大旱，1960－－1970年又是10年洪水。 这样的话，这2颗树在这20年间的年轮模式应该相似－－－尽管他们寿命不同，但是他们曾经生活在同一个时代。 他们的年轮模式可能是10个小圈圈，然后跟着10个大圈圈。。。。

            Often, ring patterns of dead trees of different, but overlapping, ages can be correlated to provide an extended index of past climate conditions.

 different ages： 1000岁和200岁

overlaping ages: 1950-1970这20年， 1807－－2007这200年，都是overlaping的。

楼上MM这个黑体完全是定位精确。

第二段讲了年轮机制的局限性，特列。

TF可能是 true or false的意思把。什么Term不重要，关键还是对   逻辑意思  和  原文基本事实   的把握。

A就是原文的复述。其他的不是无关项，就是过度推理，要不就是和基本事实相左。