4 sentences

1. 他的态度发生了巨大的转变。

   tā de tài​du fā​shēng le jù​dà de zhuǎn​biàn.

   His attitude has undergone a major transformation.

   Source: Dong Chinese Dictionary

2. 较之以往，他的态度有了很大转变。

   jiào​zhī yǐ​wǎng, tā de tài​du yǒu le hěn dà zhuǎn​biàn.

   Compared to before, his attitude has changed significantly.

   Source: Dong Chinese Dictionary

3. 这个国家的政体在几十年前转变成为了共和国。

   zhè gè guó​jiā de zhèng​tǐ zài jǐ​shí nián qián zhuǎn​biàn chéng​wéi le gòng​hé​guó.

   The country's system of government transformed into a republic decades ago.

   Source: Dong Chinese Dictionary

4. 该地区正努力实现从高速增长向高质量发展的转变。

   gāi dì​qū zhèng nǔ​lì shí​xiàn cóng gāo​sù zēng​zhǎng xiàng gāo​zhì​liàng fā​zhǎn de zhuǎn​biàn.

   The region is striving to transition from high-speed growth to high-quality development.

   Source: Dong Chinese Dictionary