这把梯子是可伸缩的，可以根据需要调整高度。

This ladder is ___extendable, so you can adjust its height as needed.

这份合同的有效期是可以延长的。

The validity period of this contract is ___extendable.

这个表格是可扩展的，你可以根据需要添加更多列。

This table is ___extendable, allowing you to add more columns as needed.