polite you Germany fly forty

（1）The books about cooking are those

Germans'

Germans'

.
（2）—What is the number of your

flight

flight

to Shanghai？
        —I haven't known yet.I have just booked one on the website.
（3）We shouldn't speak to the teachers and parents

politely

politely

.
（4）My aunt looks very young in her

forties

forties

.
（5）—Did you enjoy

your

your

trip in Hong Kong？ —Yes，we had lots of fun.