Definition
Used to indicate that something is certain to happen.
必定，势必
If we persevere, we cannot but succeed.
如果我们坚持下去，我们必然会成功。
If we remain true to ourselves, we cannot but prevail.
如果我们忠于自己，我们必然会胜利。
With people of this caliber on our side, surely we cannot but win.
有这样高水平的人在我们这边，我们必然会赢。