be on guard什么意思啊？？
be on guardkeep guardstand guard分别是什么意思、？意思都是相等的吗？可以做同义句转换吗？ 谢啦！on guard:
a. 值班(警戒)
例句与用法:
1. While danger threatens we must all be on guard.
危险正逼近，我们必须保持警惕。
2. There are soldiers on guard at the gate.
大门口有士兵在守卫。
3. Be on guard when somebody flatters you.www.souquanme.com
有人奉承你时, 一定要当心。
4. The citizens were warned to be on guard against a sudden night attack.
市民们得到通知，要提防夜间的突然袭击。
keep guard为“站岗”的意思
stand guard为“承担保卫”的意思
不相等
a. 值班(警戒)
例句与用法:
1. While danger threatens we must all be on guard.
危险正逼近，我们必须保持警惕。
2. There are soldiers on guard at the gate.
大门口有士兵在守卫。
3. Be on guard when somebody flatters you.www.souquanme.com
有人奉承你时, 一定要当心。
4. The citizens were warned to be on guard against a sudden night attack.
市民们得到通知，要提防夜间的突然袭击。
keep guard为“站岗”的意思
stand guard为“承担保卫”的意思
不相等
be on guard是什么意思
be on guard
防范
双语例句
1.
How to be on guard against pickpockets and swindlers?
乘坐地铁时如何防范扒窃和诈骗行为
2.
The prince should be on guard against them and fear them as if they were declared enemies, because they will always help to bring about his downfall in adverse times.
君主应该防范他们，对他们感到害怕，把他们当作公开的敌人来对待，因为在困难时期他们总会促搜趣网成他的垮台。
防范
双语例句
1.
How to be on guard against pickpockets and swindlers?
乘坐地铁时如何防范扒窃和诈骗行为
2.
The prince should be on guard against them and fear them as if they were declared enemies, because they will always help to bring about his downfall in adverse times.
君主应该防范他们，对他们感到害怕，把他们当作公开的敌人来对待，因为在困难时期他们总会促搜趣网成他的垮台。
有没有on guard
on guard
on guard:
a. 值班(警戒)
例句与用法:
1. While danger threatens we must all be on guard.
危险正逼近，我们必须保持警惕。
2. There are soldiers on guard at the gate.
大门口有士兵在守卫。
3. Be on guard when somebody flatters you.
有人奉承你时, 一定要当心。
4. The citizens were warned to be on guard against a sudden night attack.
市民们得到通知，要提防夜间的突然袭击。
on guard:
a. 值班(警戒)
例句与用法:
1. While danger threatens we must all be on guard.
危险正逼近，我们必须保持警惕。
2. There are soldiers on guard at the gate.
大门口有士兵在守卫。
3. Be on guard when somebody flatters you.
有人奉承你时, 一定要当心。
4. The citizens were warned to be on guard against a sudden night attack.
市民们得到通知，要提防夜间的突然袭击。
be on用法
be on
上映；演出；在进行；（灯）亮着；接受打赌
be on
1. (放置、装置、固定)在顶上：
The lid is on tightly.
盖子盖紧了。
2. 开着；燃着：
The light is on.
灯亮着。
3. 【法律】(法庭审案、案件等)安排，被审理，被提出：
There is a case on in Courtroom No 1.
有案子在第1号法庭里审理。
4. 发生；进行，举行：
This newspaper tells us what's on in and out of the country today.
这份报纸告诉我们今天国内外发生了什么事情。
5. 放映；演出：
There's a new film on in the cinema this evening.
电影院里今晚放映一部新影片。
6. (戏剧)上演；(演员)登场；(球队队员)出场：
She is on next.
她下一个登台。
7. 同意，同意参加某计划、活动等：
Shall we go for a walk? ——OK,I'm on.
我们散散步好吗? ——行，我同意。
8. 上班；值班：
Two soldiers must be on guard all night.
两名战士必须通宵警戒。
9. 参加，参与；就位，到位[亦作 be upon]:
He is on first base.
他在第一垒。
10. (经常)服药，用药[亦作 be upon]:
Father has been on that medicine for several days.
父亲几天来都在服www.souquanme.com用那种药。
11. 由…支付[亦作 be upon]:
This meal is on 搜趣网me.
这顿饭由我付账。
12. 【板球】(开始)投球：
Jack was on for three more overs.
杰克投了三次球。
13. (赛马)把…押下打赌；对…打赌[亦作 be upon]:
Their money is on Tolson to win the final race.
他们的钱都押在要赢得最后一轮比赛的托尔森的身上了。
14. 留着：
The scars are still on me.
我身上仍留着疤痕。
15. 使焦急，使烦恼：
That matter is always on my mind.
我对那件事总是放心不下。
希望我的回答 对你有所帮助 如有疑问 请在线交谈 祝你：天天开心 心想事成 O(∩_∩)O ...
上映；演出；在进行；（灯）亮着；接受打赌
be on
1. (放置、装置、固定)在顶上：
The lid is on tightly.
盖子盖紧了。
2. 开着；燃着：
The light is on.
灯亮着。
3. 【法律】(法庭审案、案件等)安排，被审理，被提出：
There is a case on in Courtroom No 1.
有案子在第1号法庭里审理。
4. 发生；进行，举行：
This newspaper tells us what's on in and out of the country today.
这份报纸告诉我们今天国内外发生了什么事情。
5. 放映；演出：
There's a new film on in the cinema this evening.
电影院里今晚放映一部新影片。
6. (戏剧)上演；(演员)登场；(球队队员)出场：
She is on next.
她下一个登台。
7. 同意，同意参加某计划、活动等：
Shall we go for a walk? ——OK,I'm on.
我们散散步好吗? ——行，我同意。
8. 上班；值班：
Two soldiers must be on guard all night.
两名战士必须通宵警戒。
9. 参加，参与；就位，到位[亦作 be upon]:
He is on first base.
他在第一垒。
10. (经常)服药，用药[亦作 be upon]:
Father has been on that medicine for several days.
父亲几天来都在服www.souquanme.com用那种药。
11. 由…支付[亦作 be upon]:
This meal is on 搜趣网me.
这顿饭由我付账。
12. 【板球】(开始)投球：
Jack was on for three more overs.
杰克投了三次球。
13. (赛马)把…押下打赌；对…打赌[亦作 be upon]:
Their money is on Tolson to win the final race.
他们的钱都押在要赢得最后一轮比赛的托尔森的身上了。
14. 留着：
The scars are still on me.
我身上仍留着疤痕。
15. 使焦急，使烦恼：
That matter is always on my mind.
我对那件事总是放心不下。
希望我的回答 对你有所帮助 如有疑问 请在线交谈 祝你：天天开心 心想事成 O(∩_∩)O ...
you should certainly be on your guard against thieves。。。be on your guard本身就是戒备防备的意思，
为什么还要用agains他也是,防备;预防的意思you should certainly be on your guard 不能直接跟宾语。必须加against意思是防备
附against意义：介词 prep.
1.反对;违反
The fight against cMSHZwinflation has been going on for almost two years.
抑制通货膨胀的战斗已展开近两年了。2.逆;对着
They sounded a sharp warning against all these tendencies.
对于这种种倾向,他们发出了严厉的警告。3.倚;靠
His desk is against the wall.
他的办公桌靠墙放着。4.以...为背景
The little red house looks so beautiful against the green woods.
那座红色的小屋在翠绿的森林衬托下显得很美。5.防备;预防
We bought some warm clothes against the coming winter.
我们添置了一些御寒的衣服以迎接即将来临的冬季。6.不利于
She has said nothing against you.
她并没有说任何对你不利的话。
附against意义：介词 prep.
1.反对;违反
The fight against cMSHZwinflation has been going on for almost two years.
抑制通货膨胀的战斗已展开近两年了。2.逆;对着
They sounded a sharp warning against all these tendencies.
对于这种种倾向,他们发出了严厉的警告。3.倚;靠
His desk is against the wall.
他的办公桌靠墙放着。4.以...为背景
The little red house looks so beautiful against the green woods.
那座红色的小屋在翠绿的森林衬托下显得很美。5.防备;预防
We bought some warm clothes against the coming winter.
我们添置了一些御寒的衣服以迎接即将来临的冬季。6.不利于
She has said nothing against you.
她并没有说任何对你不利的话。
