Question 38:

• "When we (remember) to reserve a table." This is a past action that happened before another past action. So, we need the past perfect tense.

• "When we (get) to the restaurant, we (find) that nobody..." This is a sequence of actions in the past. We can use the simple past tense for both verbs.

• Complete sentence: When we had remembered to reserve a table, when we got to the restaurant, we found that nobody...

Question 39:

• "I could tell at a glance that the pile of letters on my desk..." This is a past action.

• "...while I (be) out." This is a past continuous action that was happening while another past action occurred.

• Complete sentence: I could tell at a glance that the pile of letters on my desk had been disturbed while I was out.

Question 40:

• "As soon as she arrived England, she..." This is a past action that happened immediately after another past action.

• "...(find) that the language..." This is the main verb of the sentence and should be in the simple past.

• "...(be) quite different from the English that she (learn) at school." This is a past perfect tense because the learning of English happened before she arrived in England.

• Complete sentence: As soon as she arrived in England, she found that the language was quite different from the English that she had learned at school.