convex bottom造句

They were all characterized as having a concave top portion and a convex bottom portion.
Their hypothesis relies heavily on the suggestion that large lunar craters, generally assumed to be formed from meteor impact, are generally too shallow and have flat or even convex bottoms.
The facets, convex bottom, and the shiny inner surface catch as much available light as possible, reflecting it throughout the wine in the cup, making it possible to see through the wine.
"Tingmiatornis " also differs from " Ichthyornis " in the following ways : the fossa of the humerus is deeper; and the expansion of the humerus known as the bicipital crest is longer, with a slightly convex bottom edge that transitions smoothly into the rest of the humerus rather than being hatchet-shaped.
It's difficult to find convex bottom in a sentence. 用convex bottom造句挺难的