Combining the following three sentences by using a cohesive device: Tom's work at school is above the average. Harry's work is below the average. Tim's work is about up to the average.

Combining the following three sentences by using a cohesive device: Tom's work at school is above the average. Harry's work is below the average. Tim's work is about up to the average.

Tom's work at school is about the average, while Harry's is below that, and Tim's is about up to it.