1 Change down into second as you approach the corner.

2 Change down before you get to the hill.

3 You have to change down when you drive uphill.

4 Change down into second.

5 You must change down now.

6 I must change down now.

7 He came back and laid the change down with the food.

8 You have to change down when you drive up a slope.

9 Pressing heavily on the pedals, the bicycle would then do what is not required,(www.Sentencedict.com) namely change down.

10 I'm not an experienced driver and even have to change down on small hills.

11 So it's not clear whether this will lead to more meaningful change down the road.