例句與造句

1. The arch of the aorta forms two curvatures : one with its convexity upward, the other with its convexity forward and to the left . Its upper border is usually about 2.5 cm . below the superior border to the manubrium sterni.
2. Each transverse sinus passes lateralward and forward, describing a slight curve with its convexity upward, to the base of the petrous portion of the temporal bone, and lies, in this part of its course, in the attached margin of the tentorium cerebelli; it then leaves the tentorium and curves downward and medialward ( an area sometimes referred to as the sigmoid sinus ) to reach the jugular foramen, where it ends in the internal jugular vein.
3. It's difficult to find convexity upward in a sentence. 用convexity upward造句挺難的