第12句：Of course,the conditions of work are very different:The Ponlytechnic is offering two-year contract which could be renewed,but the language school is only offering a year's contract,and that's a different minus.

六級詞匯講解:
該句較長，出現在長對話之中。of course放在句首或句末時起強調作用。offer意為“提供”，通常指主動提供。which引導的是two-year contract的定語從句，其中renew意為“使繼續有效;延長期限”。minus此處意為“缺點”，是該句的聽音難點所在。

六級考點歸納：
minus作名詞時，有以下含義:
1.“負號，減號”。如:
Don't forget the minus when you add them up，
求和時別忘了負號。
2. “不利條件，不足，缺點”。如:
We should consider the pluses and minuses of the system.
我們應該考慮一下該系統的優點和缺點。