That is the only way I can explain his behavior.

I asked the local person we were with to explain that young man's behavior.

Even those who knew him couldn't explain his behavior on the morning of August 25, 1883.

The theory is concerned with how people explain their behavior.

That's the only way I can explain his behavior at that death conference.

"Do you want to explain your behavior on the bridge just now?"

Which offered nothing in the way of explaining her behavior.

Does she have a story to tell that would explain, even justify, her behavior?

"I wonder if these things he doesn't want us to know about might explain his strange behavior around here."

She was obviously at a loss to explain my strange behavior.