We have to protect animals because of ecosystem

We have to know first what animals do for us.
>> This is a good sentence.

Frankly, like lion or panda, they don\'t help us directly.
>> Frankly, animals, like lions or pandas, don\'t help us directly.

However, even mosquitoes they are vital animals for ecosystem.
>> However, they are vital for the ecosystem, even mosquitoes.

If there are not mosquitoes, in the case of dragonflies that eat harmful insects for us, the prays for them will decrease a lot.
>> Dragonflies eat harmful insects like mosquitoes. If there were no mosquitoes, their prey would decrease in number.

So if some animals are extinct, there will be bad effects to ecosystem.
>> If some animals become extinct, there will be bad effects on the ecosystem.

It says we have to protect them not to be extinct.
>> We have to protect them so they will not vanish.

 We can avoid this bad situation as protecting the animals not to be endangered.
>> No need to write this. It\'s the same as the sentence before it.

The best way to protect them is prohibiting the poaching.
>> The best way to protect them is to prohibit poaching.

The reason of being extinct is poaching.
>> It is the reason for extinction.

So we can punish poaching people by imposing finance to them.
>> We can punish poachers by imposing fines.

 In conclusion, we have to protect animals because of ecosystem, and the best way is imposing finance to poacher.
>>  In conclusion, we have to protect animals for the ecosystem, and the best way to do that is to impose fines on poachers.