3 sentences for 解体 (jiě​tǐ — collapse)

1. 苏联于1991年解体。

   Sū​lián yú yī​jiǔ​jiǔ​yī​nián jiě​tǐ.

   The Soviet Union dissolved in 1991.

   Source: Dong Chinese Dictionary

2. 苏联在1991年正式解体。

   Sū​lián zài yī​jiǔ​jiǔ​yī​nián zhèng​shì jiě​tǐ.

   The Soviet Union officially disintegrated in 1991.

   Source: Dong Chinese Dictionary

3. 前苏联在1991年正式解体。

   qián Sū​lián zài yī​jiǔ​jiǔ​yī​nián zhèng​shì jiě​tǐ.

   The former Soviet Union officially dissolved in 1991.

   Source: Dong Chinese Dictionary