Present and future tenses

Example:
Today Datca has grown considerably. Its population reaches 6,000 in winter. The town has developed so much that there are many cafes, bars and restaurants there now. They are building a three-lane road now and it is about to finish. When the road has finished (instead of will have finish, or will have been finished), a lot more people will come to that seaside town and more summer houses will be built and more cafes and bars will open. I believe it will be good for the locals, but people who know (instead of knows, meaning 'people' is not considered as single third participant) the past of the town may not welcome the change.

In this example you are going to experience present simple, present perfect simple and future perfect tenses. Remember when describing daily habits we use simple present tense. When we talk about the things we have completed, especially if we mention the number of things completed, we use present perfect simple. Finally, if we describe things that are expected to be completed in the future, we use future perfect.
Example:
We consume small amounts of food daily. But when you make calculations, the amount a single person consumes in his life time turns out to be amazing, even frightening.
Let's give an example. I am 30 years old now, and I drink a liter of water a day. That means I drink 365 liters a year. So far, I have drunk 10,950 liters, i.e. more than ten tons of water. By the time I am (instead of will be) 60, I will have drunk 22 tons of water and by the time I am (instead of will be) 90, this will have reached 33 tons.
Another example is eggs. If you eat 2 eggs a week, that makes 104 eggs a year. Again I have eaten about 3,120 eggs up to now. By the time I reach (instead of will reach) 60, I will have consumed 6,240 eggs. Great consumers we are, aren't we?

Reference