Write the words into the gaps:

1. Lucy: Yes, everything's ready. We're going to have a great picnic! Sophie,

brought the CDs?

2. He’s

them in that bag.

В зависимости от контекста. Время не влияет на артикль.
Если ты говоришь о кенгуру в обобщающем значении, то неопределённый артикль a, а если в конкретизирующем значении, то определённый артикль the.

A kangaroo is one of the most unique animals in the world. (Кенгуру является одним из уникальнейших животных в мире)

The kangaroo seems to be hungry. (Кажется, этот кенгуру голоден)

В выражении "What a nice kangaroo" всегда неопределенный артикль, в выражении "How nice the kangaroo is" всегда определенный артикль.

Hello, my dear friend!
  Thank you for your letter. Don’t worry that you are writing me only a few months later after getting my letter.
 I know that Christmas time is always a very busy period as you have to buy many presents for your friends and relatives, to finish all your work. I hope that your Christmas holidays won’t be awful because of your sister and her family. I know that in your heart your love your niece and nephew very much. I am sure you will have a great time together!
 My family and I - we wish you a Merry Christmas! I wish you to be healthy and lucky! I hope to get a letter with some nice photos of you and your family.
 Kind regards,
yours Anna