~ばいい for suggestions


I am aware that ~ばいい can be used to suggest or imply something. For example,
in the sentence:

> 自分ですればいいだろ (Do your own work)

However, I tried to make the sentence: Come with her to the party / It is good
that you come with her to the party

> 彼女とパーティに行けばいいですね

But I was told that this sounds unnatural, and I should therefore say:

> 彼女とパーティに行けるといいですね (another conditional!)

My questions:

  * Any conditional can be used for generating this suggestions?

  * Is there any rule so that we know which conditional should we use in each case? Because I don't understand why my sentence is unnatural.




(First, the Japanese verb for "come" is "来る" not "行く", but for now we'll
pretend that "go(行く)" is our verb.)

"彼女とパーティに行けばいいですね。" sounds unnatural because you used the wrong discourse
particle "ね" at the end. (It's not wrong-wrong, actually, but... unnatural, if
only for the nuance you are trying to convey.) For the function of "ね", see
Yuuichi Tam's answer.

The right choice would be "よ" or not to use any at all. (The nuance varies
between with and without it, but not too greatly.) Apart from that, your
sentence is perfectly fine:

> 彼女とパーティに行けばいいです(よ)。 ("It will be good if you go to the party with her." Or
> less literally, "You **should** go to the party with her.")

Whoever told you to rewrite it as "彼女とパーティに行けるといいですね。" slyly converted the
verb to the potential form (行ける: can go), along with the ば→と change. As a
result something more than a little nuance was altered. Namely, the sentence
turned from a suggestion/advice to an expression of hope!:

> 彼女とパーティに **行ける** といいですね。 ("It will be good if you **can** go to the party
> with her." Or less literally, "I _hope_ you **can** go to the party with
> her.")

The difference in meaning is due to the change not in the conditional word
(ば→と) but rather in the verb form. (And look what an impact it makes on the
semantics of the whole sentence!)

You can replicate the same change in meaning without swapping the conditional
word. You need only to change the verb form to the potential (and the
discourse particle to "ね"):

> (1a) 彼女とパーティに **行けば** いいです(よ)。 (You should go to the party with her.)  
>  (1b) 彼女とパーティに **行ければ** いいですね。 (I hope you can go to the party with her.)
>
> (2a) 彼女とパーティに **行くと** いいです(よ)。 (You should go to the party with her.)  
>  (2b) 彼女とパーティに **行けると** いいですね。 (I hope you can go to the party with her.)




(First, the Japanese verb for "come" is "来る" not "行く", but for now we'll
pretend that "go(行く)" is our verb.)

"彼女とパーティに行けばいいですね。" sounds unnatural because you used the wrong discourse
particle "ね" at the end. (It's not wrong-wrong, actually, but... unnatural, if
only for the nuance you are trying to convey.) For the function of "ね", see
Yuuichi Tam's answer.

The right choice would be "よ" or not to use any at all. (The nuance varies
between with and without it, but not too greatly.) Apart from that, your
sentence is perfectly fine:

> 彼女とパーティに行けばいいです(よ)。 ("It will be good if you go to the party with her." Or
> less literally, "You **should** go to the party with her.")

Whoever told you to rewrite it as "彼女とパーティに行けるといいですね。" slyly converted the
verb to the potential form (行ける: can go), along with the ば→と change. As a
result something more than a little nuance was altered. Namely, the sentence
turned from a suggestion/advice to an expression of hope!:

> 彼女とパーティに **行ける** といいですね。 ("It will be good if you **can** go to the party
> with her." Or less literally, "I _hope_ you **can** go to the party with
> her.")

The difference in meaning is due to the change not in the conditional word
(ば→と) but rather in the verb form. (And look what an impact it makes on the
semantics of the whole sentence!)

You can replicate the same change in meaning without swapping the conditional
word. You need only to change the verb form to the potential (and the
discourse particle to "ね"):

> (1a) 彼女とパーティに **行けば** いいです(よ)。 (You should go to the party with her.)  
>  (1b) 彼女とパーティに **行ければ** いいですね。 (I hope you can go to the party with her.)
>
> (2a) 彼女とパーティに **行くと** いいです(よ)。 (You should go to the party with her.)  
>  (2b) 彼女とパーティに **行けると** いいですね。 (I hope you can go to the party with her.)

