主要问题

However, in this field of study in China there still exists five points of issues as follows:(1) the forecast of natural gas hydrate resource at the sea is exaggerated;(2) studies on hydrate reservoiring dynamics, reservoiring system, and especially the hydrocarbon source are not enough as well;(3) research on physical stratigraphy of hydrate sedimentary reservoir rocks is still blank;(4) the relationships among the BSR in the seismic profile, blind zone of amplitude, and sedimentary reservoir are still unknown;(5) the exploration technical studies are not complete and systematic yet.

但是，中国海域天然气水合物的勘探研究还存在5个方面的主要问题：海域天然气水合物资源量预测过大；对天然气水合物成藏动力学、成藏体系研究不够，尤其是对烃源研究不够；中国在天然气水合物沉积层岩石物理方面的研究几乎还是空白；对地震剖面上的BSR、振幅空白带与天然气水合物沉积层的关系仍然不是十分清楚；中国目前的天然气水合物勘探技术研究还不够深入、不够系统。

Fourthly,the paper rethinks the axiology of some western economists.

本文认为，经济学说史中各种形式的价值理论，其存在的主要问题是在由没有把有形价值和无形价值的概念区分开来。

Furthermore, the rapid increase of medical costs evidently retrains the demand for medical service.

以下是存在的主要问题：医疗资源的分配和结构不合理。

The need for strengthening and retrofitting existing structures or damaged ones is the one of the most important problems that structural engineers face.

对现有及受损结构进行加固和修复是结构工程师所面临的主要问题之一。

"My main concern is removing the perception that Venezuela is a risky place to do business, which has been exacerbated by what has happened at Las Cristinas over the last 15 years," says Mr Salamis.

萨拉米斯表示：&我关心的主要问题是消除一种看法即在委内瑞拉经商是有风险的。过去15年里Las Cristinas发生的事情又加剧了这点。&

The major problems in existence and the schemes for improvement, and

存在的主要问题以及改进的方案

This is the main problem with shields, there is no current theory as to how they would work.

这就是屏蔽武器的主要问题所在：至今没有任何理论证明它是如何运作的。

The main problem that I have is smudging everything that I write, it's the reason that I stopped writing in pencil.

现在的主要问题，我已是沾污一切，我写，这是原因，我停止用铅笔书写。

Technically, the main problems at the moment are 'phishing' or 'spoofing' scams.

技术上，目前的主要问题是'钓鱼'或'欺骗'的陷阱。

He said he was not sorry that he had made tariffs the major issue in the campaign.

他表示，他并不遗憾，他曾在竞选关税的主要问题。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！