be sure of

确信

例句与用法：

Can I be sure of a profit if I invest?

我要是投资，肯定能获利吗?

Book early if you want to be sure of a seat.

要想十拿九稳有个座位，那就早订座。

I left a message so as to be sure of contacting her.

我留下了张条子以便与她取得联系。

He likes to be sure of his bodily comforts.

他注重身体上的舒适。