we ________ _____________ started our trip earlier in the morning.

fill it in with a helping verb

had

we need two helping verbs Ms. Sue

or --

could have
should have
might have

To fill in the blank with a helping verb, we need to consider the tense and form of the sentence.

In this case, we can use the helping verb "should have" to complete the sentence:

"we should have started our trip earlier in the morning."

To determine this answer, we need to understand the concept of helping verbs and analyze the context of the sentence. Helping verbs, also known as auxiliary verbs, are used to form various tenses, moods, and voices of the main verb in a sentence. In this case, the helping verb "should have" signifies that the action of starting the trip earlier in the morning was necessary or advisable to complete it successfully.