I stumbled across a document that compares some aspects of Japanese and English. There's a particularly interesting list of metaphor-based idioms that are mysteriously common to both languages, such as 'on the same wavelength', 'hit the wall', 'close one's eyes to', 'be all ears', and a bunch of others. Since they are used the same way as in English, people should be able to pick them up pretty easily, and naturally knowing idioms is a great way to sound more natural. They are under section 3-2 of the document.
どうぞご覧になってください