Here is a list of opposites:
1) Day and Night
2) Rich and poor
3) Sea and beach
4) Read and write
5) TV and phone
6) House and flat
7) Walk and drive
8) Cat and dog
9) Car and bus
10) Sweet and savoury
With another person, choose one word each from a pair and then argue why the word you chose is better. The other will argue that the opposite thing is better. 1 or 2 minutes?