天平上的小电珠不亮,其主要故障原因是电路接触点氧化、电源插座松动等因素。
参考答案:对
用括号内所给词的适当形式填空。
小题1:My birthday is on the ________ (five) of June.
小题2:Look! There are some books on these ________(shelf).
小题3:There is ________(little) money in this pocket than in the one.
小题4:The book doesn’t belong to ________(he), his book is on his desk.
小题5:At weekends, there are so many ___________(shop) in the supermarkets.
关系操作的特点是 【5】 操作。