Sentence 1: Bob had stacked twelve cinder blocks near his driveway. 
 Sentence 3: Bob got tired of seeing them there 
 Sentence 4:  He offered the cinder blocks to a friend 
 Sentence 5:  Bob delivered them to her house when she accepted the offer 
 Option 1: His friend came and picked them all up the next morning. 
 Option 2: They sat for weeks and crushed all the grass under them.