The city needs one more, defined as scoring below 101, to reach its goal of 245 Blue Sky days this year.

这个城市只需要再增加一天，空气污染指数低于101，就可以达到今年245个蓝天的指标。

youdao

The number of official “blue sky days” is on the rise, and the ubiquitous whiff of coal smoke is now rare.

官方统计的“蓝天日”的数量在上升，以前随处可见的袅袅炊烟现在变得罕见了。

youdao

Beijing has reported four blue sky days so far in April, challenging the target of achieving 230 clean air days a year.

迄今为止，北京四月份已经报告有四个蓝天，挑战一年230个空气清洁日的目标。

youdao

Mullins went on to release several LPs, including 1992's Better Days and 1994's Big Blue Sky.

NPR: From Station XPN: Shawn Mullins in Concert

The architects painted the cables white, so that they would disappear into the sky on overcast days, and complement the blue of clear skies.

WSJ: A Concrete Ribbon Through the Clouds | Millau Viaduct | Masterpiece by Joseph Giovannini

But if you hit one of those beautiful winter days when the sea is calm and the sky is blue, continue along the coast path for about two miles until it curves into the hidden bay and tiny old harbour of Lamorna Cove.

BBC: Britain's winter wanderland