His body showed a rejection reaction to the transplanted organ.

His single word triggered a chain reaction, and everything changed.

She overreacted to his words.

Nuclear reactions are used for mass production of energy.

I was surprised by his overreaction.

He solved complex mathematical problems using his new calculator.

I am working using a spreadsheet software.

His calculating nature sometimes causes problems.

Please check the statement of account.

It's difficult to solve this formula.