新政策实施后，空气质量有了显著改善。

Xīn zhèngcè shíshī hòu, kōngqì zhìliàng yǒu le xiǎnzhù gǎishàn.

After the new policy was implemented, the air quality improved significantly.

经过几个月的训练，他的进步非常显著。

Jīngguò jǐ gè yuè de xùnliàn, tā de jìnbù fēicháng xiǎnzhù.

After several months of training, his progress has been very significant.