重點講解:
1. ask sb. to do sth. 要求…(做…);請求…(做…);
Homework assignments and examinations will often ask you to explain something or to define something that you have been taught.
在作業和考試過程中,常常會要求你解釋或定義一些你已經學過的事物 。
2. be fluent in 流利的;流暢的;
She studied eight foreign languages but is fluent in only six of them.
她學習了8種外語,但是只能流利地說其中 6 種 。
3. focus on 集中(注意力);關注;
In this article, we focus on encryption and digital signatures.
本文中我們主要討論加密和數字簽名 。
n. 前提
vt. 提論,預述,假設