All the big planes need big airports for taking off and landing，without the airport，the big planes won"t WOrk.While a helicopter can both take straight up and come straight down.It needs on―ly a small place for both taking off and landing.What"s more， the heli。copteYs can stay a few feet above the groand.Can a big plane do so? Sohelicopters are sometimes more useflul than big planes.
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