Perfect Continuous #Present Perfect Continuous Verb: Walk E.g.: [+] That robot has been walking for 5 hours usually the owner calls him. [-] That robot has NOT been walking for 5 hours usually the owner calls him. [?] Has that robot been walking for 5 hours usually the owner calls him? [-, ?] Has that robot NOT been walking for 5 hours usually the owner calls him? #Past Perfect Continuous Verb: Walk
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