GWD-17-38

[lunar916]

GWD-17-38

All Y chromosomes in existence today are descended from a single ancestor’s who is thought to have lived about 140,000 years ago.

A. a single ancestor’s who is thought to have lived
B. a single ancestor’s who was thought to live
C. a single ancestor whom it is thought had lived
D. the Y chromosome of a single ancestor who is thought to have lived
E. the Y chromosome of a single ancestor whom it was thought had lived



ans: D

=====
看到的考點有
1) who vs whom
2) live vs has lived vs had lived

可是我不知道這些考點該怎麼選... @@
大家來討論一下吧~

[Kyo]

依句意，Y chromosomes 的來源應該是ancestor身上的Y chromosomes ，所以ABC都錯囉。

who is thought to -->是慣用，不需要用被動語態，所以E也有問題，至於E用受格的原因是因為他是被動。

have lived就有點詭異了，表示它活到現在...

[lunar916]

依句意，Y chromosomes 的來源應該是ancestor身上的Y chromosomes ，所以ABC都錯囉。

who is thought to -->是慣用，不需要用被動語態，所以E也有問題，至於E用受格的原因是因為他是被動。

have lived就有點詭異了，表示它活到現在...

睡一覺起來後忽然覺得用whom好像沒什麼道理...
可是如你所言,Y chromosomes 的來源應該是ancestor身上的Y chromosomes
a & b - a single ancestor's (省略Y chromosome)
這樣應該沒問題吧

不過我也覺得have live好像很怪

繼續討論

[tsaowen]

be thought to have + PP 是推測動詞的慣用法
類似的還有 be alleged to have PP
be believed to have PP

open to discuss~

[pamelatsai]

(A) (B)who的先行詞應該不能用所有格吧~

[nexxt0722]

be thought to have + PP 是推測動詞的慣用法
類似的還有 be alleged to have PP
be believed to have PP

open to discuss~

這個趕緊學起來...

選項AB中,
就形式來看,who的先行詞是所有格,奇怪!
就句意來看,所有格後面省略Y染色體,若要做為who的先行詞,還是奇怪!

[pimi]

請問D中的who是代a single ancester???

[firstlove1224@hotmail.com]

是的!
who 是指代前面的 a single ancester 表示她活了多久

[kotokolin]

句意是說現在Y染色體起源於一個祖先的Y染色體 (現在認為祖先存在140000年前)

A, B不好=> 雖然所有格後面省略了Y染色體，但who 不能指代所有格, 就算可以也不知是指祖先還是Y染色體
C不好=> 染色體起源於祖先, 句意怪異
B, E 不好=>主句用現在式，關係子句時態不該用過去式，表"現在"普遍認為was 應該為is

[ggethan]

根據mo北北講議 表推測可以有以下用法:

It seems/appears/is seen/is thought/is supposed/is believd/is known/is alleged that S+have/has Vpp

S seem/appear/is seen/is thought/is supposed/is believd/is known/is alleged that to have Vpp

所以(c)(e)應該改成it is thought that the ancestor has lived...

[dibert8]

... ancestor {(who is thought) to have lived} about 140,000 ago.
時態的問題:
who is thought (= whom we think = we think = it is thought) 插句,帶出推測時間
to have lived 推測動詞,推測時間是現在,所以用現在完成式.

想到一題:
GWD 21-34
Scientists have dated sharp-edged flakes of stone found in the fine-grained sediments of a dry riverbed in the Afar region of Ethiopia to between 2.52 and 2.60 million years ago, pushing back by more than 150,000 years the earliest date when it is known that humans made stone tools.
A. when it is known that humans made
B. at which it is known that humans had made
C. at which humans are known to have made
D. that humans are known to be making
E. of humans who were known to make