present perfect vs present continuous

[user_gary]

Please help me to choose the correct option. I think the both options are correct because I have seen in many contexts where they are interchanged.
Can I mix up the present perfect and present continuouse tense as in the above sentence?. Or it should be "were" or "have been". Please help me.

[Mister Micawber]

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Your sentence contains the present perfect and the simple present, and the sentence is fine. He 'has seen' in the indeterminate past, and the 'contexts' remain interchanged now.
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