61.【You must buy a new one for each letter you send. 】
B
62.【After the stamp has done its job, the post office says it is worthless.】
D
63.【To get one of these uncommon stamps, some collectors are willing to pay a great deal of money】
B
64. D
65. C
61.【You must buy a new one for each letter you send. 】
B
62.【After the stamp has done its job, the post office says it is worthless.】
D
63.【To get one of these uncommon stamps, some collectors are willing to pay a great deal of money】
B
64. D
65. C