海防的英文：
coastal defense

参考例句：

Coast defence ship
海防舰

fortifications of coastal defence in Ming dynasty
明代海防筑城

In Qing Dynasty Government Li Hongzhang is the main leader and practitioner of the construction of coast defense.
李鸿章是清政府海防建设的主要领导人和实践者。

coastal是什么意思：
adj. 海岸的；沿海的

They decided to fortify the coastal areas.
他们决定加强海岸地区的防卫。

San Diego is a sunny coastal city.
圣地亚哥是个阳光迷人的海滨城市.

Blue projects: Projects covering coastal and marine resources.
蓝色项目:指利用沿海和海洋资源的项目

The coastal mountains descended precipitously to the very edge of the Pacific
沿海的山脉陡峭地向着太平洋岸边延伸而下。

The radio alerted coastal residents to the dangers of the hurricane
之声提醒沿海居民注意飓风的危险。

defense是什么意思：
n. 防御，防御工事；防御物；防御措施；辩护；（比赛中的）守方
v. 抵御，防御

(in a match) the defense
守方

The defenses of the city must be strengthened.
这个城市的防御工事必须加强。

He was the then secretary of Defense.
他是当时的国防部长。

Offense is the best defense.
进攻是最好的防御。

Attack is the best form of defense
攻击是最好的防御