Теория:

To speak about things now and in the past, you need the appropriate vocabulary.
 
time-2801596_640.png
Рис. \(1\). Clock
 
century – век

original – оригинальный

tough – тяжелый, трудный

without – без

electricity – электричество

telephone – телефон

washing machine – стиральная машина

coach – карета, экипаж

clean river – чистая река

pollution – загрязнение

pure – чистый
 
Examples:
 
Many years ago people didn't have washing machines.
  
The rivers were clean and the air was pure.
Источники:
Рис. 1. Clock, https://pixabay.com/images/id-2801596/ Pixabay License CC0