hogoneko wo soto ni dasu wake ni ha ikanai.

保護猫 means a rescued cat or shelter cat—a cat that has been taken in and protected, rather than, for example, a cat that was always someone’s pet from birth.

In real usage, it often suggests a cat that was:

• rescued from the street
• taken in by a shelter or volunteer
• adopted after being rescued

So the word carries a nuance of a cat that needs protection/care.

The particle を marks 保護猫 as the direct object of the verb 出す.

Here, 出す means to put/take/let out, so the thing being let out is 保護猫.

Structure:

• 保護猫を = the rescue cat
• 外に出す = let it go outside / put it outside

So 保護猫を外に出す means to let the rescue cat outside.

Because 出す is transitive, while 出る is intransitive.

• 出る = to go out, to come out
• 出す = to put out, send out, let out

In this sentence, someone is causing the cat to go outside, so Japanese uses 出す.

Compare:

• 猫が外に出る = The cat goes outside.
• 猫を外に出す = Someone lets the cat outside.

Since the cat is the object being acted on, 出す is the correct choice.

Because 外 is the destination/location reached, so に is used.

• 外に出す = put/let something outside

The particle に marks the place something moves to.

Using を with 外 would not work here in standard Japanese. The object marker を is already used with 保護猫.

You can also sometimes see 外へ出す, where へ emphasizes direction, but 外に出す is very natural and common.

わけにはいかない is a grammar pattern meaning something like:

• cannot do
• must not do
• it wouldn’t be acceptable to do
• I can’t just do that

The important point is that it usually does not mean physical inability. It means there is some reason—moral, social, practical, emotional, or situational—that makes the action unacceptable.

So here, 保護猫を外に出すわけにはいかない means more than simple inability. It suggests:

• it would be wrong
• it would be irresponsible
• the situation does not allow it

For example, because the cat is a rescue cat, it may be unsafe to let it outside.

Yes, わけ originally means reason or logic, but in わけにはいかない, the whole expression functions as a set grammar pattern.

You do not need to interpret it word-by-word every time, but the rough idea is:

• That is not a reason/logic by which it can go
• more naturally: That’s not something one can do

So while わけ does have its basic meaning in the background, in this pattern it is best learned as part of the fixed expression dictionary form + わけにはいかない.

The は adds contrast/emphasis and is part of the standard pattern わけにはいかない.

A helpful way to feel it is:

• に connects to わけ
• は highlights it, almost like as for that reason/logic...

In practice, though, learners should treat わけにはいかない as one chunk.

So rather than analyzing it too mechanically, it is better to remember:

• V-辞書形 + わけにはいかない = cannot bring oneself to do / cannot do for certain reasons

The subject is omitted, which is very common in Japanese.

Depending on context, it could mean:

• I can’t let the rescue cat outside
• We can’t let the rescue cat outside
• You/they can’t let the rescue cat outside

Japanese often leaves out subjects when they are obvious from context. So the sentence focuses on the action and the judgment, not on explicitly naming the subject.

In many real situations, the implied subject would probably be the speaker or the people taking care of the cat.

They are different in nuance.

• 出せない = cannot let out
  This can mean simple inability: maybe you are unable, it is impossible, you do not know how, etc.

• 出すわけにはいかない = cannot allow oneself to let out
  This strongly suggests there is a reason it would be wrong or unacceptable.

So:

• 保護猫を外に出せない could sound like I can’t let the rescue cat outside
• 保護猫を外に出すわけにはいかない sounds more like I really shouldn’t / I can’t possibly let a rescue cat outside

The second one has more of a sense of responsibility or constraint.

Yes, but the nuance changes.

• 保護猫を外に出すわけにはいかない
  Focuses on the action letting the rescue cat outside and says that action is not acceptable.

• 保護猫は外に出せない
  Uses 保護猫は as the topic and means something more like As for rescue cats, I can’t let them outside or This rescue cat can’t be let outside.

The original sentence sounds more specific and more strongly tied to the speaker’s judgment or responsibility.

Japanese nouns usually do not show singular/plural clearly by themselves.

So 保護猫 could mean:

• a rescue cat
• rescue cats

In this sentence, context will decide. If you saw it alone, many people would probably imagine one rescue cat, but grammatically it does not have to be singular.

It is in the plain form.

• いかない is plain
• a more formal/polite version might be 保護猫を外に出すわけにはいきません

So the sentence as written is natural in:

• casual speech
• inner thoughts
• written narration
• everyday conversation

It is not rude by itself; it is simply non-polite.

Not exactly.

• 外に出してはいけない = must not let it outside / it is forbidden to let it outside
• 外に出すわけにはいかない = I/you/we can’t allow ourselves to let it outside

The first sounds more like a rule, prohibition, or instruction.

The second sounds more like a judgment based on circumstances, responsibility, or common sense.

So if you are talking about your own situation and feelings of responsibility, わけにはいかない is often more natural.

No. In normal Japanese writing, this would usually be written without spaces:

保護猫を外に出すわけにはいかない。

Spaces are often added in textbooks or learning materials to make the sentence structure easier to see. They are just for study, not standard writing.