stand by
phrasal verbstand by
to be present while something bad is happening but not do anything to stop it 袖手旁观；无动于衷 How can you stand by and see him accused of something he didn't do? 你怎么能眼睁睁看着他遭人诬陷呢？ Surely the world cannot stand idly by and let this country go through the agony of war yet again? 国际社会当然不能袖手旁观，让这个国家再度经历战争的伤痛吧？
to be ready for action 做好随时行动的准备；做好准备
stand by somebody
to help somebody or be friends with them, even in difficult situations 支持；帮助；忠于 her famous song, ‘Stand by your man’ 她的著名歌曲《忠于你的男人》
stand by something
to still believe or agree with something you said, decided or agreed earlier 仍然遵守诺言（或协议等）