The midclavicular line is the imaginary line that gets drawn from the midpoint of the left clavicle, or the collarbone, straight down, and you can find where it intersects with the fifth intercostal space.

锁骨中线是一条从左锁骨中间位置笔直画下来的假想线，你可以找到它与第五肋间隙相交的位置。