discover、find、detect与ascertain这些动词均有“发现”之意。
discover : 普通用词，指首次发现本来存在，但未被认识的事物、真理或情况。
- Who discovered America?
谁发现了美洲？ - We searched all morning for the missing papers and finally discovered them in a drawer.
我们一上午都在找那些失踪的文件，最后终于在一个抽屉里找到了。 - Scientists have discovered how to predict an earthquake.
科学家们找到了预测地震的方法。 - She discovered (that) her husband was having an affair.
她发现丈夫有外遇。 - Following a routine check-up, Mrs Mason was discovered to have heart disease.
例行体检发现梅森夫人患有心脏病。 - The boss discovered him stealing money from the cash register.
老板发现他从钱箱里偷钱。
find : 普通用词，可指偶然发现，也可指经过寻找后得到或重新获得已失去的东西。强调动作的结果。
- I've just found a ten-pound note in my pocket.
我刚在口袋里找到了一张10英镑的钞票。 - I couldn't find Andrew's phone number.
我找不到安德鲁的电话号码。 - You'll find the knives and forks in the left-hand drawer.
你会发现刀叉在左手边的抽屉里。 - Researchers are hoping to find a cure for the disease.
研究者们希望能找到治愈这种疾病的方法。 - Has he found himself a place to live yet?
他找到地方住了吗？ - She was found unconscious and bleeding.
人们发现她时，她已不省人事而且血流不止。 - The study found that men who were married lived longer than those who were not.
这一研究发现已婚男人的寿命要比未婚男人长。 - Do you think they'll ever find a way of bringing peace to the region?
你认为他们能找到办法给这个地区带来和平吗？ - We're really struggling to find (= get) enough money to pay the rent.
我们眼下正想尽办法凑钱缴房租。 - After years of abuse from her husband, she eventually found the courage to leave him.
在遭受丈夫多年的虐待之后，她终于鼓起勇气离开了他。 - I wish I could find (the) time to do more reading.
我希望自己能挤出时间多看一点书。
detect : 正式用词，强调经过周密观察或研究而有所获得和发现，尤指发现有意隐藏之物。
- Some sounds cannot be detected by the human ear.
有些声音是人的耳朵无法察觉到的。 - Financial experts have detected signs that the economy is beginning to improve.
金融专家已经注意到了经济开始有好转的迹象。
ascertain : 较正式用词，指有意搜寻与发现。
- The police have so far been unable to ascertain the cause of the explosion.
警方到目前为止尚未查明爆炸原因。 - Have you ascertained whether she's coming or not?
你问清楚了吗，她来还是不来？
