I made some sentences, but I am not sure whether they are right or not.
If you find something wrong in Grammar or vocabulary, help me check them.

Thank you very much

1. Professional doctors took advantage of new medical equipment to develop an anti-SARS vaccine.

2. Nowadays, it just takes tourists thirteen hours to travel from Taiwan to the United States by airplane whereas it might take a half of year to arrive in by boat in 20th century.

3. It is only when parents understand how to praise and punish thier children that they can lead their value system to be positive.

4. Taiwan’s electorate who lack cognitive skills are esaily manipulated by politicians, resulting in populism that forces them not to have the ability to see things in perspective.
I answered this already in another thread. Clive
Students: Are you brave enough to let our tutors analyse your pronunciation?
I am not expert in english sentence. I need to inspect correct sentence.

That's a good idea. Do you have an English book? It should have a lot of sentences that you can inspect.

Best wishes, Clive