handier , handiest
Something that is handy is useful.
The book gives handy hints on looking after indoor plants.
这本书提供了关于如何照料室内植物的有用信息。
A thing or place that is handy is nearby and therefore easy to get or reach.
It would be good to have a pencil and paper handy.
手边备有纸笔会很有用。
come in handy
If something comes in handy, it is useful in a particular situation.
The £20 cheque came in very handy.
这张20镑的支票正好派上用场。