Определите видовременную форму сказуемого в предложении.

[email protected] в категроии Английский язык, вопрос открыт 29.05.2018 в 16:52

1. After having made many experiments the scientists developed a new building material – glass concrete.

2. They produced the new material at the plant in 1990 and since that time people have used it widely.

3. Prestressed concrete is a subject of cracking because it enables lighter construction.

4. Examination of a piece of granite showed the shortcomings of the material.