zhè jiàn shì / guān xì / zhòng dà / nǐ / bì xū / zǐ xì / sī lǜ / hòu / zài / zuò / jué dìng

这件事关系重大，你必须仔细思虑后再做决定。

This matter is of great importance; you must think carefully before making a decision.