1Sheshavingsinginglessons她在上声乐课。2Shewasoutofpracticeatsinging她对唱歌荒疏了。3Iheardthemsinging我听见他们在唱歌。4Sheclearedherthroatandstartedsinging她清了清嗓子，唱了起来。 雅思口语part2多久