Sentence 1: Oliver went to the beach that summer. 
 Sentence 3: He was bored sitting on a chair for hours on end 
 Sentence 4:  So he signed up for a diving class 
 Sentence 5:  He spent a fabulous summer exploring under the sea 
 Option 1: He usually went to the mountain and didn't know what to do but will never explore the sea. 
 Option 2: He usually went to the mountain and didn't know what to do.