The phrase "feel comfortable doing" is correct and usable in written English. It can be used to express that someone is confident in their ability to do something. For example: "I have plenty of experience with public speaking, so I feel comfortable doing it in front of large groups.".
"But I feel comfortable doing that.
I just feel comfortable doing this".
But would enough athletes feel comfortable doing this?
"I didn't feel comfortable doing it," Ms. Pausch said.
"We don't feel comfortable doing this, complaining," she said.
Jimmy doesn't feel comfortable doing super-mean jokes.
I don't know if people feel comfortable doing that".
Thanks to Ludwig my first paper got accepted! The editor wrote me that my manuscript was well-written
Listya Utami K.
PhD Student in Biology, Bandung Institute of Technology, Indonesia