every so often

释义

偶尔，时常

在例句中理解 1 句

1. Normally loners, every so often these natives of the deserts from West Africa to India turn into vast, voracious swarms that leave hunger and poverty behind them wherever they go.

   这些来自从西非到印度沙漠的土生昆虫通常并不成群，但是偶尔也会汇集成巨大、贪婪的蝗群，它们所到之处能留下的是饥饿和贫困。