12. Read the text below. For each empty space (1-11) choose the correct answer (А, В, C or D).
At one time people (1) __________________ there (2) __________________ life on the moon and little green men on Mars. For many years some people (3) __________________ Venus (4) __________________ a natural garden because it (5) __________________ green. Some scientists (6) __________________ there (7) __________________ life in the clouds over Jupiter.
Today we (8) __________________ these things (9) __________________ true. Earth (10) __________________ to be the only planet in our solar system with life. But we will continue to wonder, “ (11) __________________ we alone?”

A В C D
1 have thought think thought has thought
2 was is were are
3 think thinks have thought thought
4 were was am are
5 are be is has been
6 thought has thought think have thought
7 were was has been have been
8 have known has known knows know
9 are not is not am not was not
10 seem seemed seems has seemed
11 Are Is Were Was