A past tense will follow only if the word “high” is inclusive but if otherwise a present tense will follow. For Example:-
1. It is “high” time we left
2. It is time we leave.
Both sentence is correct the only difference between is means that they should have gone before that time but probably due to procrastination which is why a past tense is coming after because it is what they should have done before that time in question while means the time has come for them to leave. can be used minutes after if the person is not yielding.
All the selected phrases written by you are very useful for me as well as all the readers, teachers and the students of English Literature and Language. I am very happy to read these idioms and phrases and being a very ordinary writer I Wii use these phrases to make my sentences meaningful and impressive.
Thank you very much sir for providing us these materials to read and we religiously share these beautiful phrases to our good students. Congratulations & Thanks once again & hope we will get more new phrase in this website in the days to come.
R M Jha.