How to use in-sentence of “hourglass”:
+ Only six Hourglass dolphins have been examined by scientists.
+ He was known for his cinematography works in “The Adventures of Gerard”, “The Hourglass Sanatorium” and in “Frantic”.
+ The M2 was the WWII model had hexagonal gas caps and hourglass frames.
+ Scientists thought they could take photographs of this frog to identify individual frogs, but the hourglass changes shape as the frog grows older.
+ Scientists and students use the hourglass tree frog as a test animal because it is not endangered and because it can lay eggs on land or in water.

