Answer: If you're not vegetarian, then you do not eat beef.
Step-by-step explanation:
Dismiss the 'if' and 'then':
- you do not eat beef
- you're not vegetarian
Now, all you have to do is switch their places:
- you're not vegetarian
- you do not eat beef
Now add the 'if' and 'then' back:
If you're not vegetarian, then you do not eat beef.