Use of "take on"

[Our Tort System]

Hello,

Could you tell me which sentences sound normal?

1.1. That guy is too tough, I can't possibly take him on.
1.2. That guy is too tough, I can't possibly take on him.

2.1. I can't possibly take that bulky guy on.
2.2. I can't possibly take on that bulky guy.

Thanks!
_________________
If it's not easy, don't do it!
That's how I got where I am.

[Mordant]

1.1 sounds fine, although I would punctuate it differently.

That guy is too tough; I can't possibly take him on.
That guy is too tough. I can't possibly take him on.

Although "take on" is separable, it sounds awkward used that way with personal pronouns.

2.1 and 2.2 are fine to me.

[Our Tort System]

Thank you Mordant!
_________________
If it's not easy, don't do it!
That's how I got where I am.

[Tofu]

Does the "take on" here mean "to agree to be responsible for somebody"?

[Mordant]

No, it means "to combat a problem or to challenge in competition, especially (but certainly not exclusively) in physical fights."

Congress is set to take on many divisive issues, which include illegal immigration.
In next weekend's boxing tournament, Fighter A will take on Fighter B.
The Jets will take on the Cowboys at the Super Bowl.
The small child took on his persistent bully and shockingly won.

[Tofu]

Thank you, Mordant.
The same as "take on" in "The Yankees are set to take on the Red Sox at Yankee Stadium tonight"?

[Mordant]

Yes, indeed.