ならでは vs. ぐらいのもの


I understand that both means to emphasize the uniqueness of the word before it
(i.e. "only ~") but in the following sentence, I don't know which one fits.

> この難しい手術ができるのは、渡辺先生＿＿のものだ。

Both ならでは and ぐらい seem to make sense.




`～ならではの + noun` is a set phrase meaning "(noun) only seen in ～", "(noun)
unique to ～", "(noun) that can be done only by ～", etc. For example, you can
say 渡辺先生ならではの手術, which means "surgery that can only be performed by Dr.
Watanabe." (BTW, ならでは is read ならで **わ** )

Now, this sentence is a [cleft
sentence](https://japanese.stackexchange.com/a/19208/5010) where the person
name is focused. When you say "この難しい手術ができるのは", a noun (phrase) **representing
a person** is expected after it. And 渡辺先生ならではのもの doesn't qualify as the noun
phrase representing a person.

In other words, using ならでは is wrong because it would literally mean something
like [×]"The person who can perform this difficult surgery is the thing that
can be done only by Dr. Watanabe."

`くらい/ぐらい (+ の/な + もの)` is interchangeable with だけ in cleft sentences like
this.

If you want to use ならでは, you can say
「この難しい手術は渡辺先生ならではのものだ」「これは渡辺先生ならではの難しい手術だ」, etc.




`～ならではの + noun` is a set phrase meaning "(noun) only seen in ～", "(noun)
unique to ～", "(noun) that can be done only by ～", etc. For example, you can
say 渡辺先生ならではの手術, which means "surgery that can only be performed by Dr.
Watanabe." (BTW, ならでは is read ならで **わ** )

Now, this sentence is a [cleft
sentence](https://japanese.stackexchange.com/a/19208/5010) where the person
name is focused. When you say "この難しい手術ができるのは", a noun (phrase) **representing
a person** is expected after it. And 渡辺先生ならではのもの doesn't qualify as the noun
phrase representing a person.

In other words, using ならでは is wrong because it would literally mean something
like [×]"The person who can perform this difficult surgery is the thing that
can be done only by Dr. Watanabe."

`くらい/ぐらい (+ の/な + もの)` is interchangeable with だけ in cleft sentences like
this.

If you want to use ならでは, you can say
「この難しい手術は渡辺先生ならではのものだ」「これは渡辺先生ならではの難しい手術だ」, etc.

