* The days will lengthen as we move into spring. (This sentence uses "lengthen" to describe the increase in daylight hours.)
* She lengthened her skirt by adding a ruffle at the bottom. (This sentence uses "lengthen" to describe physically making something longer.)
* The long, winding road seemed to lengthen as the sun began to set. (This sentence uses "lengthen" to describe a feeling of time or distance being extended.)
* The company is trying to lengthen its product lifespan to stay competitive. (This sentence uses "lengthen" to describe an increase in duration or time.)