atch where the space shuttle or spacecraft is parked,

Bertran said slowly:

Every year from May to September on Earth,

I will lead a group every month,

Take the interstellar travel time machine under the cosmos galaxy alien group,

Traveling to the attractions of the earth from 2020 to 2030,

The average age of the members of Space City is about 150-170 years old,

The purpose of their travels is mostly to find or investigate the millennium changes in the history of the earth...

half an hour,

The hostess Thirza said: May I ask Anita, the time traveler, what was the living environment like in 4000 AD?

Bertran paused and said,

In the year 3900 of the earth's Gregorian era,

The civilization stage of the earth has entered the first level for the first time,

Humans want to enter the first stage smoothly,

From the first stage to the second stage,

is not an easy thing,

There are two main threats,

It is worth thinking about how to deal with the earth's human beings,