Many cities use parks and farmland to build houses. Is this a positive or negative development?

No.

Negative is the opposite of positive, which is negative, negative, unfavorable and hinders development. Not enterprising, depressed From section 3, chapter 5 of Guo Moruo's Hongboqu. Chapter 5 of Guo Moruo's Red Rice Bo: On the positive side, singing can unite one's own strength. On the negative side, singing can distract the morale of the enemy.

Hao Ran's Sunny Day Chapter 93: Everyone thinks that besides those bad elements, Sun, an idle person, is also a negative factor.