know from

基本解释

I know from conversations with other smokers that this is not unusual.
我知道，这是一场对于其他吸烟者的不寻常的谈话。
Dieticians know from their experience that it is very difficult to reduce the usual quantity of food, which is the reason of most failures.
膳食专家从他们的经验知道，要减少日常的进食量是十分困难的。这正是大多数人减肥失败的原因。
You know from this result that inserting this type of string would not result in a successful login attempt, so the site is not vulnerable to this type of attack.
从这个结果可以知道，插入该类型的字符串不会导致成功的登录尝试，所以站点不容易受到这种类型的攻击。

We see that you know from everyone,they say their interest in science begins before the age of eleven.
So, we know from our calculation that we can do over here, that this bond is polar.
我们通过计算都知道,这个键是非极性的。
麻省理工公开课 - 固态化学导论课程节选
it just so happened that two other people I know from back home transferred the same time I did.
刚好我在家认识的两个人也和我同时转过来了。
留学生的适应期 - SpeakingMax英语口语达人

Ms. GALBREATH: ...it's a different mind-set from the people that I know from the Midwest.
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