sadly

adv. tristemente, abatidamente, afligidamente, desmayadamente, lánguidamente, luctuosamente, melancólicamente, mustiamente

Ex: Sadly, the information network has not so far been able to respond adequately to the special needs of business.

= lamentablemente, desafortunadamente, tristemente
Ex: Sadly, the information network has not so far been able to respond adequately to the special needs of business.
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* be sadly missed = echar muchísimo de menos, echar muchísimo en falta, echar mucho de menos, echar mucho en falta