Civil War, directed by Anthony and Joe Russo, could amass $200 million or more by Sunday, days before it launches in North America on May 6.

【参考译文】

罗素兄弟执导的大片《美队3 内战》票房到本周日（4月30号）有望突破2亿美元，届时，距离其在北美的公映日5月6号尚有时日。

【参考解析】

Civil War, directed by Anthony and Joe Russo, could amass $200 million or more by Sunday, days before it launches in North America on May 6. =

Civil War, directed by Anthony and Joe Russo, could amass $200 million or more by Sunday, by which time it’s days before it launches in North America on May 6.

我们只能说这里的关系代词which与Sunday为同位关系，而不能说days. 实际上我们没有必要分析其语法作用，一定要说，通常我们把其分析为非限制性定语或补充性状语。