phrases unique to a particular language are called idioms or an idiom
This phrase means that there is a great event. As said" We stand today at the threshold of a great event both in the life of the United Nations and in the life of mankind."So the main idea is that this ceremony or service is very important to the United States and the United nations.
The reason why Mary and Colin are happy about Susan Sowerby's visit is C,. She treats them like they are her own children.
<h3>What is a Narration?</h3>
This refers to the storytelling that is made about the events of a story and the preceding events.
Hence, we can see that from the complete text, there is the narration of the relationship between Susan Sowerby who acts like a mother to Mary and Colin and comes to help in the garden.
Read more about the Secret Garden here:
brainly.com/question/9029452
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