omitting "that"?

These that's are optional:

(1) Obama is the one (that) she thinks should be voted for.
(2) Obama is the one she thinks (that) she should vote for.

Mister MicawberThese that's are optional:(1) Obama is the one (that) she thinks should be voted for.(2) Obama is the one she thinks (that) she should vote for.

So the first that is always optional, and the second that is not permitted in (1) but is optional in (2), right?
(1-a) Obama is the one (that) she thinks that

Yes.

So the first that is always optional, and the second that is not permitted in (1) but is optional in (2), right?
(1-a) Obama is the one (that) she thinks that should be voted for. (X)
(1-b) Obama is the one (that) she thinks should be voted for. (O)
(2-a) Obama is the one (that) she thinks that she should vote for.(O)
(

JungKimI really don't understand why we should treat the two thats differently, both seemingly leading a relative clause.Is there anyone who would clarify this?

The point you're missing is that the two thats have different functions. The first one is a subordinator introducing a relative clause, and the second is a subordinator introducing a content cla

In (1-a), if we omit the first that, we get:
(1-c) Obama is the one she thinks that should be voted for. (X)
In (2-a), if we omit the first that, we get:
(2-c) Obama is the one she thinks that she should vote for.(O)

BillJJungKimI really don't understand why we should treat the two thats differently, both seemingly leadi

my question is why treat these two thats differently in their omissibility?

You don't need to treat them differently in their omissibility:

(1-c) Obama is the one she thinks that should be voted for.
(2-c) Obama is the one she thinks that she should vote for.

I'm not clear why you think tha

(1-c) Obama is the one she thinks that should be voted for.
(2-c) Obama is the one she thinks that she should vote for.

BillJI'm not clear why you think that 1-c is ungrammatical. In fact both examples are grammatical.

You might want to go back to my earlier posts in this thread, where Mister Micawber answered my first few questio

JungKimYou might want to go back to my earlier posts in this thread, where Mister Micawber answered my first few questions

I'm afraid that MM made a slip there. Obama is the one she thinks that should be voted for is definitely grammatical.

BillJ

BillJI'm afraid that MM made a slip there. Obama is the one she thinks that should be voted for is definitely grammatical.

I am with Mr M here. That sentence sounds very strange to me.