切入点的英文：
point of penetration; breakthrough point

参考例句：

Ecological construction was the fundament of economic development.
生态建设是经济发展的根本和切入点。

point是什么意思：
n. 点；标点；要点；尖端；得分
v. 削尖；指向；加标点于；表明

That is not the point in question.
那不是要考虑的要点。

orientation point
方位点

A score made on a try for a point or points after a touchdown.
触地得分在触地后再次发球所得的一分或几分

penetration是什么意思：
n. 渗透；突破；洞察力

tip penetration
磁头尖插入度

The nail will not penetrate.
这枚钉子钉不进去。

These are the result of the penetration of the larvae into the crypts
这些是幼虫钻入滤泡的结果。

breakthrough是什么意思：
n. 突破

to make a breakthrough; to breach
攻破

Such a speedy breakthrough is rare in the history of science.
这也是科学史上罕见的快速突破。

The scientists strive for a breakthrough in cancer research.
科学家们力争在癌症研究方面有个突破。