选择短语，并用其适当形式完成下列句子
get off be out of date know about shoot at be short for take off
1．The plane ________ from the airport and headed north towards Zhengzhou.
2. He ________the target but missed it.
3．Cassette tape recorders ________now. Fewer and fewer people are using them.
4．NATO ________ North Atlantic Treaty Organization.
5．How much do you ________ Singapore? And why do you want to work here?
6．Not until I ________ the bus did I realize that I had left my bag with my laptop on the bus.
1．took off 2.shot at 3.are out of date
4. is short for 5.know about 6.got off