He is unpredictable, weeping one moment, laughing the next.
⇑ Translate the sentence above by Google ⇑
Related: unpredictable, weep
Prev: take into account the seasons as well as any unpredictable weather. New seeds must be sown and weeds must be pulled.
Next: Unfavorable conditions that are relatively predictable probably pose a simpler problem for organisms than do unpredictable conditions.