if he allowed me i would have shoped
can you simply explain what time does it show &
when else would have can used
Would have normally relates to some action or 'thing' that that didn't occur in the past because some other event didn't occur in the past. ie. it is conditional on something else having happened.
ie. everything is in the past.
Put simply: If this event HAD occurred then that event would have occurred. That is all in the past.
However, you could use would have to describe what your reaction to what might have been in the future, given some other event which could be either in the past or in the future but WHICH DIDN'T OR WILL NOT HAPPEN. (ie...you are imagining yourself looking back on a different past which might have happened but wasn't really real).
This might be a description of what you would have done in the Summer Holidays if (ie conditional on) you win the lottery or had already won the lottery. In this case, you'd be describing a history (ie. in the past) of something which didn't happen, either in the past, or in the future.
In short, would have describes your reaction to a imaginary event in any time scale.