Pete Walker is a professor at the University of Bath in Britain.

VOA: special.2009.10.05

Every time you do the experiment T in equilibrium with the heat bath at T, v2 you'll get the same p2 and V2.

与热库相接触的每次实验中,达到热平衡后的温度都是，压强都是p2，体积都是。

麻省理工公开课 - 热力学与动力学课程节选

And here, in an isothermal expansion, The bath is putting back the energy that the gas is expanding or using to expand, and so the energy is flowing back into the gas through the environment in the isothermal expansion.

而在等温膨胀中，恒温环境将气体膨胀对外做功,而损失的能量又返还回来，在等温膨胀中,能量从环境,流向系统。

麻省理工公开课 - 热力学与动力学课程节选