be able to 4

[John]

Are these all OK and natural?

1-1. I can finish this (by) tomorrow.
1-2. I'll be able to finish this (by) tomorrow.
1-3. I'm able to finish this (by) tomorrow.

2-1. I can't finish this (by) tomorrow.
2-2. I'll not be able to finish this (by) tomorrow.
2-3. I'm not able to finish this (by) tomorrow.

Thanks.

[Rusty]

Are these all OK and natural?

1-1. I can finish this (by) tomorrow.
1-2. I'll be able to finish this (by) tomorrow.
1-3. I'm able to finish this (by) tomorrow.

2-1. I can't finish this (by) tomorrow.
2-2. I'll not be able to finish this (by) tomorrow.
2-3. I'm not able to finish this (by) tomorrow.

Thanks.

(1-1, 1-2 and 2-1, 2-2 are OK. The meaning changes with or without by. 1-3 and 2-3 Sound incorrect).