to move through the air, or to travel by aircraft.

(a)  

an extremely large, round mass of rock and metal, such as Earth, or of gas, such as Jupiter that moves in a circular path around the sun or another star.

(a)  

the empty area outside earth's atmosphere, where the planets and the stars are.

(a)  

one of the independent groups of stars in the universe.

(a)  

the mark of the foot or the movement or sound of each step a person takes when walking

(a)  

the area above the earth, in which clouds, the sun, etc. can be seen.

(a)  

an organized journey for a particular purpose.

(a)  

very good.

(a)  

below the surface of the earth; below ground.

(a)  

you are not free or available to do something.

(a)  

willing to give money, help, kindness, etc., especially more than is usual or expected.

(a)  

a discovery is also something that you did not know about before.

(a)  

nervous and uncomfortable with other people.

(a)  

being a large distance from top to bottom or a long way above the ground, or having the stated distance from top to bottom.

(a)  

very exciting to look at.

(a)  

needing to drink something.

(a)  

a machine controlled by a computer that is used to perform jobs automatically.

(a)  

wanting or needing food.

(a)  

land not in towns, cities, or industrial areas, that is either used for farming or left in its natural condition.

(a)