賢い in English:

He's wise.

Early to bed, early to rise makes a man healthy, wealthy and wise.

Religion is regarded by the common people as true, by the wise as false, and by the rulers as useful.

Idleness, which is often becoming and even wise in the bachelor, begins to wear a different aspect when you have a wife to support.

When we deal with people, it would be wise to try to separate the sheep from the goats without letting them know it.

Wise men talk because they have something to say; fools, because they have to say something.

If the life and death of Socrates are those of a wise man, the life and death of Jesus are those of a God.

He who thinks himself already too wise to learn from others will never succeed in doing anything.

A prudent bird chooses its tree. A wise servant chooses his master.

Don't grow old, grow wise!

someone who is wise makes good decisions, gives good advice etc, especially because they have a lot of experience of life

A wise man once said, "If Esperanto is an artificial language, then my car is an artificial horse".

Is it really wise for marketing folks to satisfy people's desire for instant gratification?

To persuade somebody that your recommendation is reasonable and wise, you have to give reasons and quote known examples and authorities.

Wise men talk about ideas, intellectuals about facts, and the ordinary man talks about what he eats.