Explanation:
To complete the sentence using a superlative, we need to compare the day to all other days in the speaker's life and indicate that it was the happiest. The superlative form of the adjective "happy" is "happiest." By using "the" before the superlative form, we are showing that we are comparing it to all other days and declaring it as the happiest day.
Step-by-step solution:
1. Read the sentence: "It was a very happy day. It was _____ of my life."
2. Identify the adjective that needs to be in the superlative form. In this case, it is "happy."
3. Change the adjective "happy" to its superlative form. The superlative form of "happy" is "happiest."
4. Add "the" before the superlative form to indicate that we are comparing it to all other days and declaring it as the happiest day.
5. The completed sentence is: "It was a very happy day. It was the happiest of my life."
It was the happiest day of my life .