It is hard to imagine Gina Qiao, Lenovo’s talkative head of human resources, at a loss for words. But when her employer announced, following its acquisition of IBM’s personal computer division in 2005, that it was adopting English as the company language in place of Mandarin, she was speechless.

“It was the toughest time of my whole life,” she recalls in rapid accented English, punctuated by the occasional malapropism and mixed-up tense. “I couldn’t communicate. I couldn’t express my ideas. Because I couldn’t say anything, I just felt maybe I am not so smart.”

The feelings of frustration and loss of confidence that threw Ms Qiao off her stride are an increasingly unfortunate feature of a global marketplace that has elected English as the de facto language of international exchange. As managers create teams that straddle national borders, knit together companies that are merging and look for ways to speed up the sharing of knowhow, their attempts to impose a common language on a multilingual workforce can create winners and losers.