“I took that on.”

When to use it

Describing volunteering for something nobody owned.

What it replaces

"Nobody was doing it so somehow I ended up doing it…"

The hedged version is not wrong English. It is English that asks the interviewer to do the work of deciding whether you meant it. The confident version makes the decision for them.

In an answer

“The audit prep had no owner. I took that on and had the binder ready ten days early.”

How to make it automatic

1. Say it aloud five times now, at normal speed, with contractions.
2. Pick one story from your own work where it fits, and say that story once using it.
3. Record a 60-second answer tomorrow and listen for whether it came out on its own.