At a more pragmatic level, tools for working with XML schemas are less mature than those for working with DTDs (especially regarding validation, which is the core issue).

从更实际的角度来说，用于XML模式的工具不如用于DTD的工具来得成熟(特别在确认方面，这是核心问题)。

youdao

Climate change is the core issue of global change, and it has aroused widespread international attention.

气候变化是全球变化的核心问题，已经引起了国际社会的广泛关注。

youdao

Finance is the core issue of mergers and acquisitions.

财务问题是企业并购的核心问题。

youdao

"Unless we solve the core issue of the Israeli-Palestinian, Israeli-Arab challenges then we will always be an area of instability that costs all of us,".

VOA: standard.2009.04.26

Clinton says preventing the exploitation and marginalization of girls is no longer an afterthought but a core foreign policy objective of the United States, which is co-sponsoring a Security Council resolution on the issue next week.

VOA: standard.2009.09.25

The quantity and quality of the food we eat, although significant, is not the core issue.

BBC: Americans are getting fatter faster than ever before.

The core issue is that the Cyprian banking system, in fact the whole Eurozone banking system was and is an accident waiting to happen.

FORBES: Cyprus, Anything But Unique and Why to Worry

Telling this story induces so much backlash that I typically just tell an incentive story unless financial reform itself is the core issue we are discussing.

FORBES: Don��t Follow The Money: The Hunt for the Roots of the Global Financial Crisis