The astronaut did many experiments in the spaceship, great help for knowing more about space.
A. which we think it is B. which we think is of
C. of which we think is D. we think which is of
The astronaut did many experiments in the spaceship, great help for knowing more about space.
A. which we think it is B. which we think is of
C. of which we think is D. we think which is of
B
略