Please be here at seven o'clock sharp.

　　請七點(diǎn)整到這里。

　　I shall be calling for you at seven o'clock.

　　7點(diǎn)鐘我來接你。

　　At seven o'clock the night nurse came in to relieve her.

　　7點(diǎn)鐘的時候夜班護(hù)士來接她的班。