The exhibition is timely, since 'self-taught' art is catching on in a big way.此次展览非常及时, 因为“自学艺术”正大行其道。

The recent outbreaks of cholera are a timely reminder that this disease is still a serious health hazard.最近的霍乱爆发及时警示人们：这种疾病仍严重威胁着健康。