A heated debate has been arouarisedn on whether the modified one-child family control policy areis beneficial to our society or not.

And I hold the positive side opinion that the modified policy might bring about the positive change.

Those who declare worried abouexpress concern about the policy argue that the overall population will be blow outexplode because of the policy.

It is not entirely clear what you are trying to say in the original sentence here. I hope my correction captures the original meaning. Important to note is that "declare worry" is not a common phrase. Instead, consider "express concern" here. The sentence also needs to be expanded a bit to make it clear who you are talking about and what they think.

However, they ignore the fact that our economy will be pace-slow down due to the elder-age labor souaging workforce if our government does not take any action to the situation.

"Aging workforce" is a common phrase that is used to describe that the working population is getting older.

This sentence sounds more natural without the last few words. If you want to say something about the situation, you would typically say "address" the situation rather than "take action to the situation."

In addition, under the one-child family policy will accelerate turning the society into aging societ, society will age more quickly, which will damage the population structure.

the first part of the sentence sounded a bit unnatural - this is one rephrasing that makes it clearer.

What’s more, when the modified policy came out, the public reaction iwas not exciting and up-coming newnthusiastic and subsequent birth rates showsed that the modified policy iwas not efficient, which means the worry is uselessmisguided.

keep an eye on the tense of your verbs so that they all match in the sentence.

Considering theses factors, what we should be worriedy about is that our government should not only propagateimplement the new policy, but also supply the “by-product”,necessary support for families, such as increasing paid leave days for parents or provide moreing a higher birth allowance for younger parents.

All in all, I support the modified policy because ofthe one-child family control policy is not longer suitable for China now.

However, based on the reaction of the public, our government should publishrovide more support to help new birth parents.