know exactly about sth.
參考例句：
There are thousands of cycle paths in Holland.
荷蘭有數千條自行車道。
(of a verb)have different forms showing number,tense,etc
(指動詞)有數、時態等詞形變化
There are several matters that claim my attention.
有數樁事值得我注意
Man remained a hunter for thousands of years.
人類的狩獵時期有數千年之久。
He has been peddling from house to house for weeks.
他挨家挨戶作小販已有數星期。
The area has been mined for slate for centuries.
這個地區開採板岩有數百年了。
There are millions of American veterans from the Second World War.
有數百萬參加過第二次世界大戰的美國退伍軍人
Millions of cattle are slaughtered every day.
每天有數百萬頭牛被屠殺。
Millions of tons of slag now go into building roads each year.
每年有數百萬噸爐渣用於鋪路。
Hundreds of people gathered in the open to watch the film.
有數百人聚集在露天看那部電影。
know是什麼意思：
v. 知道，瞭解，懂得；認識，熟悉；認出；體驗；見到過，聽到過
Learn not and know not
不學無術
Know/not know what is most important and act accordingly
能[不能]按輕重緩急行事
Do you know that lady?
你認識那位夫人嗎？
exactly是什麼意思：
adv. 確切地；究竟；正是如此
three exactly coincident rasters
三個精確一致的光柵
Exactly: and that is the ineluctable modality of the audible
正是這樣。這就是可聽事物無可避免的'形態。
You can do exactly as you like.
你愛怎麼做就怎麼做。
about是什麼意思：
prep. 關於；大約；從事於；在…到處
adv. 附近
adj. 在附近的；即將...的
There was nobody about.
附近沒有人。
Stereotypes about adultery are as common as research about it is flaky.
奇怪的是：這種陳詞濫調和關於通姦的研究一樣普遍。
She has a complex about rats.
她對老鼠有病態恐懼。
