脸上下得来to not take offence (Britain); to not take offense (US)

• 你当面挖苦人，人家脸上磨得开吗？

  was he not put out by you having a dig at him?

好意思to not feel embarrassed

• 她请客你不去，你磨得开吗？

  didn't you feel embarrassed at not turning up after she invited you?

想得通to be convinced