Select the correct helping verb to complete the sentence.
The sight of its hair, along with the state of its clothing, ___________ made it difficult for Annie to trade her doll in.
Although I usually run in the evening, I decided to go in the morning because of the weather. It has been so hot this summer; so hot in fact, that I cannot run in the evening. Therefore, until we have cooler weather, I will continue to enjoy a morning run.
What tense are the verbs in this paragraph?