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Date: Saturday, 28th September

Weather: cool and windy

This morning, Uncle Bob and I went on a ride in his helicopter(直升机). The helicopter lifted us up gently and quickly. It was fast.

First, we were over Whiteway. I saw many factories there. There was a lot of smoke from the factories. The air was dirty. Then we flew to Blueway. I saw many buildings there. I also saw a river beside a large park. The air in the field was clean. After that we flew to Yellowway. There were many construction sites (建筑工地) and a lot of dust (灰尘). The air was very dirty.

At last we flew back to Greenway. There were many ships in the harbour (港口). The air in Greenway was also very dirty. Our city is beautiful, but the air is dirty. We must keep it clean.