And why is the English title of this series "The summer you were there", while the Japanese title "君と綴るうたかた"
Both titles are Japanese (you can see the former on the covers and next to chapter titles). It's trendy to have a secondary or tertiary Latin alphabet title on the cover, be it a mere romanization, a clumsy literal translation, or a wholly unique subtitle, with a chance of it sounding natural.
The English publisher probably just chose one over the other, with a small chance of the licensor pushing for it..
That said, it's a standard practice to localize titles to fit the target language, culture or publisher's market research better, with no requirement to preserve anything from the original title.
Thank you for your explanation, I keep wondering if the Japanese title has "Utakata", but the English version doesn't have the word "Singing", or the English word "Summer" but the Japanese version doesn't have "Natsu", so are two titles with different meanings
I haven't seen anyone reply to you, so just a heads up that the title says nothing about singing; the word is うたかた, not うたった (or better yet, 歌った). うたかた is "fleeting, ephemeral" and 綴る is in this context composing/writing (as in writing a book), so the translation would be something akin to "Briefly / fleetingly writing with you", which is very tough - in my opinion - to translate into good sounding title in English.
