have deep roots and luxuriant leaves—be well established and vigorously developing ? 我們兩國(guó)人民之間的友誼～，并將萬(wàn)古長(zhǎng)青。The friendship between our two peoples is now well established and vigorously developing. It will remain fresh forever.
根深葉茂gen shen ye mao
have deep roots and thick foliage—be well eastablished and flourishing
根深葉茂ɡēn shēn yè mào
茂：繁茂。根扎得深，葉子就繁茂。比喻基礎(chǔ)牢固，就會(huì)興旺發(fā)達(dá)。be well established and vigorously developing, have deep roots and luxuriant leaves, thick with leaves and deep-rooted