Regrettably. In a manner deserving or inspiring lamentation.(adverb)
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Use "lamentably" in a sentence
"Kenyan President Mwai Kibaki on Friday ordered the civil service to implement a new affirmative action campaign to boost what he called a lamentably low number of women employed in the public sector."
"The answer of "neither," lamentably, is not available."
"But, lamentably, that is not the political world we inhabit."