When I (arrive) at the party, everyone (already / leave). She (not / see) him since he (move) to another city. By the time we (get) to the cinema, the film (already / start). If he (study) harder, he (pass) the exam last year. They (wait) for the bus when it (start) to rain. I (just / finish) my homework when the phone rang. He (live) in London for five years before he (move) to New York. We (watch) TV when the power (go) out. She (always / want) to visit Paris, and last year she finally (do) it.

When I arrived at the party, everyone had already left.
— arrived — Past Simple: действие произошло в определённый момент в прошлом.
— had already left — Past Perfect: все ушли до того, как я пришёл.

She has not seen him since he moved to another city.
— has not seen — Present Perfect: она не видела его с определённого момента в прошлом и до настоящего времени.
— moved — Past Simple: переезд произошёл в прошлом.

By the time we got to the cinema, the film had already started.
— got — Past Simple: мы пришли в кинотеатр.
— had already started — Past Perfect: фильм начался раньше нашего прихода.

If he had studied harder, he would have passed the exam last year.
— Это условное предложение третьего типа, описывающее нереальную ситуацию в прошлом.
— had studied — Past Perfect в части с условием.
— would have passed — результат, который мог бы произойти, но не произошёл.

They were waiting for the bus when it started to rain.
— were waiting — Past Continuous: длительное действие происходило в определённый момент в прошлом.
— started — Past Simple: короткое действие прервало или сопровождало ожидание.

I had just finished my homework when the phone rang.
— had just finished — Past Perfect: домашняя работа была закончена непосредственно перед звонком.
— rang — Past Simple: телефон зазвонил после этого.

He had lived in London for five years before he moved to New York.
— had lived — Past Perfect: он жил в Лондоне в течение пяти лет до переезда.
— moved — Past Simple: затем он переехал в Нью-Йорк.

We were watching TV when the power went out.
— were watching — Past Continuous: просмотр телевизора был длительным действием.
— went out — Past Simple: электричество внезапно отключилось.

She had always wanted to visit Paris, and last year she finally did it.
— had always wanted — Past Perfect: желание существовало долгое время до поездки.
— did — Past Simple: в прошлом году она наконец осуществила своё желание.