There's a tradition of having parties ... (on /in /at /for) Christmas

1/There's a tradition of having parties ... (on /in /at /for)Christmas.
2/Gernerally,rice is served(to/at/in/with )....fish,meat,soup and
vegetable.
3/You...(needn'd/can't/don't have to/mustn't) speak when the
teacher is speaking.
4/Christmas Eve is the day (that/which/when/what)people in some
countries exchange their parents.
5/Japanese have developed the custom of eating meals sitting on
tatami..(towels/prongs/trays/mats),not on chairs.
6/You have to...(take off/put on/break with/get out)your hat when
going inside the main worship area of the temple.
7/You...(shouldn't/don't have to/should/mustn't)place your
chopsticks on your rice bowl when finished with a meal.Don't rest
them on the table.
8/He...(followed/obliged/reflected/agreed)a long family tradition
of serving the military.
9/In the UK, families often celebrate Christmas together,...
(though/but/because/so)they can watch each other open their
presents!
10/" We don't sweep the floor on the first day of Tet!"(what a bad
day!/ You're kidding!/You're right!/Spot on! Why?
11/You look really tired. You (should/must/have to/can)take a few
days off and have a holiday.
12/In Viet nam, you (mustn't/don't have to/should/shouldn't)take a
deep bow as you do in Japan.
13/Sorry,but my train is at 6.00.I(shouldn't/ought to/mustn't/have
to)leave now.
14/You (shuoldn't/don't have to/mustn't can't)look at other
students' work. It's against the rules.
15/The airline only allows two pieces of luggage. You
(shouldn't/mustn't/don't have to/couldn't)pack too much.
16/John can't come because he(should/can/must/has to)work
tomorrow.
17/I know they enjoy their work,but they(shouldn't/don't have
to/mustn't/have to)work at the weekends. It 's not good for them.
18/Elderly people(shouldn't/should/aren't obliged to/mustn't)be
treated with great respect.
10/II (morat/le