制作和审核出口单据的主要依据是什么
参考答案:合同、信用证、《UCP600》、《ISBP》、其他相关制单资料。
若方程组有解,则其中a=()。
A.-2
B.-1
C.1
D.2
用所给单词的适当形式填空
l. Doctors often tell us ( drink) more water every day.
2. The medicine must _ ( keep) away from children.
3. Be quiet ! The baby fell _ ( sleep).
4. There must be some _ ( visit) in our friend' s home.
5. The weather says tomorrow is _( wind) .