It's only a medium-sized city. It's only a medium-sized city.

It's only a mediumn average sized city. It's only an average sized city.

It's only a medium-sized city. It's only a medium-sized city.

Yes, Anhui is a province, and it is almost as large as a country in Europe. Yes, Anhui is a province, and it is almost as large as a country in Europe.

It's probably larger than some European countries.

In China, it can only be placranked about 100 th or so. In China, it can only be ranked about 100 th.

Your sentence is correct but 'rank' is more precise.

In China, it canis only be placed aabout 100 th or soin size. In China, it is only about 100th in size.

"Placed at" would not be used here. In terms of content, your answer is a little confusing; even though it's only 100th among Chinese cities, apparently the city itself has about 2 million people and the prefecture has 8 million. This size would be considered large in many other countries.

In China, it can only be placed at 100 th or soYou can consider it to be perhaps the hundredth largest city in China. You can consider it to be perhaps the hundredth largest city in China.

Better phrased : You can consider it to be perhaps the hundredth largest city in China.

In China, it can only be placed att's probably around 100 th or soin size in China. It's probably around 100th in size in China.

There are no mountains, and all it has is plenty of farmland. There are no mountains, and it has plenty of farmland.

Your sentence sounds awkward; sorry but I can't say exactly why!

There are no mountains, and all of it has is plenty of farmland. There are no mountains, and all of it has plenty of farmland.

Yes, I have already noticed that being an online teacher is not easy because the competition between online teachers is fierce, and some of them offer cheaply priced lessons, especially those who are from South Africa and the Philippines. Yes, I have already noticed that being an online teacher is not easy because the competition between online teachers is fierce, and some of them offer cheaply priced lessons, especially those who are from South Africa and the Philippines.

you could also say "cheap lessons" although "cheaply priced" sounds more natural

Yes, I have already noticed that being an online teacher is not easy because the competition between online teachers is fierce, and some of them offer cheap pricvery affordable lessons, especially to those who are from South Africa and the Philippines. Yes, I have already noticed that being an online teacher is not easy because the competition between online teachers is fierce, and some of them offer very affordable lessons, especially to those who are from South Africa and the Philippines.

Yes, I have already noticed that being an online teacherteaching online is not easy because the competition between online teachers is fierce, and some of them offer cheap price lessons, especially those who aree teachers from South Africa and the Philippines. Yes, I have already noticed that teaching online is not easy because the competition between online teachers is fierce, and some of them offer cheap price lessons, especially the teachers from South Africa and the Philippines.

Minor fixes to flow nicer.

Although China has good control of the Covid-19, people still don't dare to travel too much, unless it's necessary, because they fear being infected by the virus. Although China has good control of Covid-19, people still don't dare to travel too much, unless it's necessary, because they fear being infected by the virus.

covid-19 no 'the' because it is a proper name , or 'the pandemic', 'the epidemic'

Although China has good control of the Covid-19, people still don't dare to travel too much, unless it's necessary, because they fear being infected by the virus. Although China has good control of Covid-19, people still don't dare to travel too much unless it's necessary, because they fear being infected by the virus.

"the" is not typically used with "Covid-19." It is used with "virus." would not put comma before "unless"

Although China has good control of the Covid-19, people still don't dare to travel too much, unless it's absolutely necessary, because they fear being infected by the virus. Although China has good control of the Covid-19, people still don't dare to travel too much, unless it's absolutely necessary, because they fear being infected by the virus.

Although China has good control of the Covid-19Covid-19 under control, people still don't dare to travel too much, unless it's necessary, because they fear being infected by the viruscatching it. Although China has Covid-19 under control, people still don't dare to travel too much, unless it's necessary, because they fear catching it.

"being infected by the virus" is correct but long.

Yes, I still keep communicatingin touch with my penpals. Yes, I still keep in touch with my penpals.