Thisoday at noon, I saw the French buttonwood trees when I drove across Yinghuai Avenue.

It reminded me of thea scene many years ago.

In the early 80 's, I studied in a technical secondary school in the city where I now live now.

My city back thenBack then, this city was very small.

"My city" isn't grammatically wrong, but in this context it sounds a bit awkward.

It only covered only about 16 square kilometers and withhad a population inside the city of abroutnd 160,000.

No need to specify a population is "inside the city" as the word already implies that.

The most prosperous roadimportant street was Renmin Road, and it seemed like there was no other second prosperous roadn't a second most important one.

Used "street" to replace one of the "road"s, since repeating the same word in quick succession sounds too repetitive.

The attractive scenerylandmark of Renmin Road was the French buttonwood trees.

"Attractive scenery" isn't wrong but sounds kind of awkward.

It wa's worth mentioning that the branches of the trees from twoon both sides of the road could connect together, which was like a long tennnected in the middle, forming a canopy that shadowinged the whole road, soentire street. Therefore, even ion the hottest summer day, you would feel cool when you walk on the roadalking there.

Changed some wording and broke it into 2 sentences for better flow.

In the early 90 's, a new mayor was intook charge of the city.

He cut all off the buttonwood trees and planted thein palms.

I didon't know whetherif he was right or not, but the palms did bring us a kind ofprovided a different kind of feeling, and it felt like we were in a southern city.

I don't know when the palm trees were cut off later on, andlater cut, or by whom.

I also don't know what the trees are online Renmin Road right now.

MyThis city has already become ten times larger than it used to be, and my home is a littlesomewhat far from there.

Again, "my city" isn't grammatically incorrect, but since I changed it previously, for consistency it's changed here as well.

That is why now I don't know what trees are on Renmin Road arenow.

In China haese, there is an idiom "沧海桑田" (cāng hǎi sāng tián), which means time changes everything, and even the sea can become farmland.

Unrelated to sentence correction, but thank you for not including the word "mulberry" in your translation of 沧海桑田.

In the early 80 s, I studied in a technical secondary school in the city where I live now.

It covered only about 16 square kilometers and, with a population inside the city of about 160,000.

The most prosperousain road was Renmin Road, and it seemed like there wasere no other second prosperousmain roads.

I'm not entirely sure what you mean by 'prosperous' in this context. People may tend to say 'main road', 'busy road' if most of the shops and businesses are there. If you mean many rich people live there or many expensive establishments are on that street, you could say 'wealthy'.

It was worth mentioning that the branches of the trees from two sides of the road could connect together, which was like a long tent shadowing the whole road, so even in the hottest summer you would feel cool when you walked on the road.

In the early 90 s, a new mayor was in charge of the city.

He cut down all off the buttonwood trees and planted the palms.

I didn't know whether he was right or not, but the palms did bring us a kind of different feeling, it felt like we were in a southern city.

I don't know when the palm trees were cut off later on, andlater cut down, nor by whom.

I also don't know what therees // what type of trees are on Renmin Road right now.

That is why now I don't know what trees are on Renmin Road are.

You could say "This is why I no longer know what trees are on Renmin Road"