Use telephone as short as you can. Ask permission to call back home on important and urgent cases and try to use it on collect call basis.

电话：使用家中电话请长话短说。若为重要且紧急之事件需打电话回国时，应于取得接家庭许可后方可使用，并应自费，尽可能用对方付费的方式或预先购买国际电话预付卡。

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And then suddenly, after only a month's wait, there was telephone call from the OVIR office informing us that the visas were granted and we should come and collect them.

BBC: Could exit permit change speed up reforms in Cuba?