QUESTION: Fix punctuation: I wanted to get my hands dirty and make predictions and get the experimentalists to test them because I knew that the scientific community would never take a theory seriously unless it was capable of being tested experimentally
ANS: I wanted to get my hands dirty, and make predictions, and get the experimentalists to test them, because I knew that the scientific community would never take a theory seriously unless it was capable of being tested experimentally.

QUESTION: Fix punctuation: The Verandering is a gaffelgetakelte Ketch
ANS: The "Verandering is a gaffelgetakelte Ketch.

QUESTION: Fix punctuation: In the middle of the night comes welded Incredible but true
ANS: In the middle of the night comes: welded! Incredible but true.

QUESTION: Fix punctuation: The heightadjustable prop provides additional stability
ANS:
The height-adjustable prop provides additional stability.