Inventions and creations refer to scientific researchers working on the basis of practice () and obtaining results that have not been obtained before and have certain uses.
选项:
A:to explore areas that are not previously explored
B:to carry out work that has not been done before
C:to solve problems that have not been solved by previous people
D:to complete tasks that are not previously completed
发布时间:2024-05-14 19:16:31