I also feel 4 is the most awkward one, but I don't how to explain why it's wrong. Can you help me?
Q. Choose the most unsimilar expression => A:4
1. It's time you went to the meeting!
2. It's time to go to the meeting!
3. It's time you should go to the meeting!
4. It's time you go to the meeting!
5. It's time for the meeting!
1. It's time you went to the meeting!
2. It's time to go to the meeting!
3. It's time you should go to the meeting!
4. It's time you go to the meeting!
5. It's time for the meeting!
#4 is wrong because it's wrong. 'It's time (that)' requires a past tense form after it.
#3 is not very natural; 'It's time for you to go ...' is also possible.
Context is always important; labelling is rarely important.