189. On December 17, 1903, the Flyer ________near Kitty Hawk, North Carolina, with Orville Wright as pilot.
a. took off
b. it took off
c. taking off
d. took it off
190. Comets are relatively small celestial bodies ________ up chiefly on dirt and icy materials.
a. make
b. made
c. they make
d. make them
191. Researchers have long debated about ________ moon Titan contains hydrocarbon oceans or lakes.
a. Saturn’s
b. whether it is Saturn’s
c. whether Saturn’s
d. whether Saturn’s is a
- The abrasively action of the wind wears away softer layers of rock.
- There are two way of making a gas condense: cooling it or putting it under pressure.
- Researchers have discovered that the application of bright light can sometimes be uses to overcome jet lag.
- Salmon migrations may include having to jump up waterfalls, swim up rapids, or climbing fish ladders at dams.
- If a strike is called in violation of an existing contract between labor and management, its a wildcat strike.
- Snapping turtles are easily recognized because of the large head, the long tail, and the shell that seems insufficiently to protect the body.
- The long string of genes making up a chromosome have been likened to a string of pearls.
