1. The guests had, of course, realized this from the moment Bessie opened the door for them and, long before the final catastrophe, had had a difficult time trying to conceal their amusement.
    客人们自然从贝西为他们开门那一刻起就看出来了，在好长一段时间里，即最后这个乱子发生前，他们努力克制才没笑出声来。

2. You can´t conceal the truth forever.
    你不能永远隐瞒真相。

3. I had no intention of buying one, but I could not conceal the fact that I was impressed by the size of the diamonds.
    我根本不想买，但我不能掩饰这样一个事实：其钻石之大给我留下了深刻的印象。

4. Frank could hardly conceal his excitement, for he knew that he had made a real discovery.
    弗兰克几乎无法掩饰自己兴奋的心情，因为他明白自己发现了一件珍品。