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airstrip – n. an area of land that is used as a runway for airplanes to take off and land
alarm – v. to cause (someone) to feel a sense of danger : to worry or frighten (someone)
defuse – v. to make (something) less serious, difficult, or tense
contribution – n. something that is given to help a person, a cause, etc.
dredge – v. to remove mud from the bottom of (a lake, river, etc.) in order to deepen it or to search for something
pledge – n. a serious promise or agreement
