Wordly Wise - Lesson 4 - Level 6

Helicopters, hummingbirds, and blimps have something in common. All three can stay in place by ________ in the air.

Blimps and hot air balloons are very different from each other. A balloon has to go wherever the wind takes it, whereas a blimp is ________ by its two engines.

Blimps offer television viewers a bird's-eye view of sporting events. They can remain ________ above the stadium for as long as necessary.

Companies, with something to advertise, like blimps. They offer a(n) __________ way of showing off the company's message to the people below.

Blimps are used to take air samples at different heights. The purpose of this is to see how much the air is being ____________ by natural and human causes.

Blimps are not useful as weapons of war. They are so big and slow-moving that they would be unable to __________ an enemy attack.

The blimp's air bag is filled with helium. Once the bag has been _______, the helium stays inside until major repairs are needed.

Hydrogen is an even lighter gas than helium. It is not used in blimps because it is highly ______________.

A blimp stays on the ground except during calm weather. Because it is lighter than air, it is easily _________ by strong winds.

A blimp usually stays outside while on the ground. It swings from its ___________ so that it always faces into the wind.