(1) Past Continuous 係過去進行式....常用於2種動作同時進行.... eg.: Mary was reading while John was writing. oR Mary was reading while the telephone rang.
(2) Present Perfect 係指1 D過去gE 動作....而D動作會影響到現在....... eg. Paul has written a letter to Mary a minute ago. [因為Paul 岩岩寫左信比Mary 所以佢暫時5會寫]
亦適用於事實(fact) eg.:太陽從東方升起....係不變gE事實
1. was /were +ing (e.g was swimming)
2. has/have +pp(e.g. have broken)
3.The first one was happening or was doing at a particular moment in the past. As for the second one, it has just happened not long ago.