linear

温度和时间呈现出明显的线性关系。

Temperature and time show a strong ___linear relationship.

老师用粉笔在黑板上画了一条直线。

The teacher drew a ___linear line on the blackboard with chalk.

我们需要一根线性尺子来测量这条直线的长度。

We need a ___linear ruler to measure the length of this straight line.