Is this a correct sentence (english grammar)?
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"I'm desperately waiting for the Nikon D3100 to arrive in Hungary. The 1080p HD Filming is simply amazing."
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I'm desperately waiting for the Nikon D3100 to arrive in Hungary, amazing is an understatement when talking about the 1080p HD Filming.
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Yes! That is correct
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It is gramatically correct but you should use looking forward to instead of waiting for, cause looking forward to something it means that you expect something in the future with excitement and pleasure.
"I'm desperately looking forward to the Nikon D3100's arrival in Hungary. The 1080p HD filming is simply amazing."
Have a great day.