1. This is a superlative sentence.

e.g. Mr. Pitt is the heaviest of the three.

2. This is a comparative sentence.

e.g. Emily is taller than Bob.

3. This sentence is in the past tense, so you should use the past form of 'go'.

e.g. He (went) to the movies yeaterday.

What is the past of 'go'? It's 'went.'
That's right. Write 'went' in the parentheses.

(Are the expressions above all correct? Would you check them,please?)

All correct, yes!! Very nice!

(Just add a comma after "e.g." each time --

e.g., Emily is taller than Bob.

And "yesterday" was spelled incorrectly.

Yes, the expressions provided in your question are correct.

1. The sentence "Mr. Pitt is the heaviest of the three" is an example of a superlative sentence. It compares Mr. Pitt's weight to the weight of two other individuals and states that he is the heaviest among them.

2. The sentence "Emily is taller than Bob" is an example of a comparative sentence. It compares Emily's height to Bob's height, indicating that Emily is taller than Bob.

3. The sentence "He (went) to the movies yesterday" is in the past tense, and the correct past form of the verb 'go' is 'went'. So, in the parentheses, you should write 'went' to complete the sentence correctly.

Overall, the expressions mentioned in your question accurately describe the grammar concepts being discussed.