maintain an impression of wealth or well-being, especially to hide the true situation
（尤指为了掩饰真实情况而）维持门面，装门面，装体面
attend an event briefly, especially as a matter of courtesy
（尤指出于礼节而）短时间到场，露面，亮相
as far as can be seen
就表面看来，就所能看到的情况而言
to all appearances, it had been a normal day.
表面上看，那是平常的一天。