他们很少回家用英文怎么说

在这种情况下，可以用这样的表达方式来表示"他们很少回家用英语":

"They don't often speak Engpsh at home."

这个表达方式的来源是由英语中的助动词"do"和否定词"not"以及副词"often"组成的。助动词"do"用于构成否定句，否定词"not"用于否定动词或动词短语，副词"often"用于修饰动词，表示频率。

例句：

"I don't often go to the gym." (我不经常去健身房。)
"She doesn't often visit her grandparents." (她不经常拜访她的祖父母。)
"We don't often have time to watch movies on weekends." (我们周末不经常有时间看电影。)