1.but

2.but

3.because

4.but

5.and

6.so

7.but

8.but

9.because

10.and

11.but

12.so

1, I like coffee but I don't like tea 
2, I can not swim but I can ski 

3, I want a new TV because the one I have now is broken 

4, I had to work on Saturday so I couldn't go to Jonh's party 

5, My name is Jame and I'm your new teacher

6, I was cold so I turned on the heater 

7, We'll have to go shopping but we have nothing for dinner

8, The history test was difficult and the English one was easy

9, We didn't go to the beach yesterday because it was raining 

10, We have a test on Monday so I'll have to study this weekend 

11, She can speak French but she can't write it 

12, She's working late next Friday, so she can come to the party