Other ways of saying "There's no point in doing something"

1. ungrammatical, so there's no point in trying to figure out what it means.

Hello:

Could the following be possible alternatives of the above sentence?3

1.1. That's ungrammatical, so it's of no use trying to... .

1.2. That's ungrammatical, so it's no use trying to... .

1.3. That's ungrammatical, so it's useless to try to... .

1.4. That's ungrammatical, so it's of no benefit to try to... .