Her English improving by the day, Z and her English lover spend several months together, although they also grow to quarrel quite often. With her nameless lover's blessing, Z takes off to spend a few weeks traveling around Europe alone, during which time she has an affair or two (or three). She and the Englishman are clearly not meant to be together. Z returns to China at the end, with much improved English and with a much broader worldview.
A Concise Chinese-English Dictionary for Lovers would have annoyed the hell out of me if the author were a Westerner, even a Westerner of Chinese descent. Z's early thoughts on the English language and what it implies about cultural differences struck me as unconvincing, more likely the product of a Westerner imagining how a Chinese person might think than that of an actual Chinese person. As it happens, though, Xiaolu Guo was born and raised in China, thus rendering my objections on those grounds rather silly.
Guo writes her novel in Z's broken English, with the linguistic proficiency growing more with each passing chapter as Z's linguistic ability grows. The book is modest and relatively short. It's hardly the most consequential book I've read this year, but it's well-done, and Guo has hit what she aimed for.