I think characteristics should an astronauts have a un waving confidence and stamina. But, also characteristics should an astronauts have a many knowledge.

Here's your corrected composition, Jimmy.  Please go over the revisions given below. Have a good evening! 

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Jean~~

                       

                               

                         What characteristics should an astronaut have? Explain.

I think characteristics should an astronauts have a un waving confidence and stamina.

>> I think the characteristics an astronaut should have is unwavering confidence and stamina.

But, also characteristics should an astronauts have a many knowledge.

>> But another important character is they should have be knowledgeable.