56 A On B In C From D Since
查看答案
52 A research B experiment C analysis D service
5 The reason for their unusual behavior. remains a puzzle.
A fact B mystery C statement D game
27 Sometimes you may find it very difficult to decide .
28 Before you lend money to your friend, .
29 If the loan is past due, .
30 If your friend refuses to return the money, .
A you can remind your friend of it via e-mail
B you can lend more money to him or her
C you must get to know why he or she needs that money
D if you should lend money to your friend
E you can call the police to settle the issue
F there is no need to maintain a friendly relation with him or her