在英语越来越重要的21世纪，学好英语成了大学生的首要目标。为帮助大学生更好地掌握英语知识，特提供以下文章：
1. The mother said she would __ her son washing the dishes if he could finish his assignment before supper.
A let down
B let alone
C let off
D let out
2. This kind of material can __ heat and moisture.
A delete
B compel
C constrain
D repel
3. Understanding the cultural habits of another nation, especially __ containing as many different subcultures as the United States, is a complex task.
A one
B the one
C that
D such
4. In order to raise money, Aunt Nicola had to __ with some of her most treasured possessions.
A divide
B separate
C part
D abandon
5. The new appointment of our president __ from the very beginning of next semester.
A takes effect
B takes part
C takes place
D takes turns