The do-gooders arrived with their unrealistic plans but had no understanding of what the local people really needed.

do-gooders 是由动词短语 do good（做好事）加上名词后缀 -er 构成的复合名词，字面意思是"做好事的人"。这个词常带有贬义色彩，指那些自以为在做好事但实际上不了解实际情况、可能帮倒忙的人，可以翻译为"自以为是的慈善家"或"空想的社会改良家"。