様(よう)がないThere's no way to, It's impossible to

The phrase "ようがない・ようもない" emphasizes that a situation or action is absolutely impossible to exist or occur and it also has a nuance of regret or disappointment. On the other hand, "がたい" suggests that an action or a situation is hard to perform or difficult to occur, but unlike "ようがない/ようもない," it hints there could be a slight possibility, albeit challenging it may be. This is generally used in negative situations or conditions.

Both ようがない・ようもない and っこない express the idea of impossibility in Japanese. However, ようがない・ようもない is generally used when you want to express the idea that 'there's no way to do' something, often referring to lack of solutions or alternatives. On the other hand, っこない is used to express the idea that 'there's no chance' or 'it's impossible that' a speculated event or situation will occur, often implying a strong sense of denial or refusal.

The phrase はずがない asserts a very strong belief that something can't be the case, often in reaction to a surprising or unexpected event. It generally conveys surprise, denial, or disbelief. On the other hand, ようがない・ようもない refers to something that is practically, physically, or logically impossible to accomplish, often expressing a sense of helplessness or despair. This phrase is used to express the impossibility of an action regardless of one's wishes or intentions.

The grammar point わけがない emphasizes that something is impossible due to a lack of logical reasoning or justification, while ようがない・ようもない stresses that there's no method or way to accomplish something. So, if you're expressing that something is impossible due to structural conditions or physical impossibilities, you would use ようがない・ようもない, but if a conclusion or assumption is logically impossible or absurd, you would use わけがない.

1) そうもない is used when something doesn't seem very likely to happen. It describes an expectation that something probably will not occur. For instance, if you're expecting rain, but the sky is clear, you might use this phrase. On the other hand, 2) ようがない・ようもない is typically used to express something that is impossible or that one cannot do, regardless of the circumstances. For example, if you've tried everything you can to solve a problem but still can't find a solution, you would use this phrase.