defend
单词辨析：
普通用词，指采取手段使某人不生病或某物不受损害等。
Physical exercise can protect you against the flu.
体育锻炼可以预防流感。
What shall I do to protect my car against rust?
怎样才能防止汽车生锈？
She closed the window to protect the books from the rain.
她关上窗户防止雨水把书淋湿。
通常指用武装力量保护，使某人、某物、某处免受袭击。
The Great Wall was once used to defend against military aggression.
长城曾用来防御军事侵略。
He was sent to defend the border three years ago.
3年前他被派去守卫边疆。
指警惕地守护以防止造成伤害、损失等。
The command told those two soldiers to guard the entrance.
指挥官叫那两名士兵守着入口。
A lioness guarded her cubs.
一头母狮守护着幼狮。
通常指保护人、企业等免受伤害或损失。
import tariffs that shield enterprises from foreign competition
保护企业免受外国竞争威胁的进口关税
His wife lied to shield him when she took the stand.
他的妻子在出庭作证的时候为保护他而撒了谎。
She drew the curtains, shielding her eyes from the sun.
她拉上窗帘，使眼睛免受阳光照射。
相关例句：
The accused has the right to defend himself.
被告有权申辩。
How the country will defend itself in the future has become increasingly important
国家将来如何能自卫已经变得越来越重要了。
The Turkish president has gone on television to defend stringent new security measures
土耳其总统上电视为严格的新安全措施进行辩护。
They are ready to defend themselves against Uncle Sam's imperialist policies
他们已做好抗击美国帝国主义政策的准备。
The individual develops behavioural means to defend himself from the enticements to establish relations with others.
个人会发展一些行为方法以使自己不受到与他人建立关系的诱惑。
Those people who took up weapons to defend themselves are political prisoners
那些拿起武器自卫的人是些政治犯。