( )是双方或多方当事人之间的协议。
A．合同
B．要约
C．邀约
D．拍卖
参考答案：A
观察图画，看看句子的意思是否符合图意，相符的画“√”，不符的画“×”。
1. 2. 3. 4. 5.
( ) 1. The is behind the closet.
( ) 2. The is on the bed.
( ) 3. The is in front of the picture.
( ) 4. The is in the living room.
( ) 5. The is in the kitchen.
BBU和RRU通过（）传输。
A、双绞线
B、同轴电缆
C、光纤
D、跳线
2.
3.
4.
5.
is behind the closet.
is on the bed.
is in front of the picture.
is in the living room.
is in the kitchen.