Answer :
To change the verbs in the sentences into past tenses, you need to adjust them accordingly. Here are the revised sentences:
(1) The officer ordered all those who felt afraid of death to return to the trenches.
(2) I wondered what he had done with the money I lent him.
(3) He did everything he could to show us that he was a true patriot.
(4) She could not cook unless she had a good fire.
(5) Whatever the boy had done, he did not deserve so heavy a punishment.
(6) He ran so fast that he was soon out of breath.
(7) I inferred from what he said that he was not in a mood to listen to sound reasoning.
(8) It was evident that he was a lunatic.
(9) They took him for a swindler, though in fact he was quite honest.
(10) I felt surprised at what I saw.
(11) I did not see how you would be able to do this.
(12) One day a wolf really came and then the boy began to cry.
(13) He ate a good breakfast and then rang the bell for his horse.
(14) A horseman rode past, and saw what they were doing.
(15) He behaved nicely at the table, talked gently, remained cheerful, thought of others first, kept an eye on all the company, and tried to be pleasant and polite in every way.