You can learn a lot about their tactics and possible melds by keeping an eye on their draws and discards. An opponent may be attempting to form particular sets or runs if, for example, theyrummy gold - indian routinely select particular suits or ranks from the discard pile. With this knowledge, you can modify your strategy by keeping cards that might help them finish their melds or discarding cards that are less likely to help them. Also, watching opponents involves more than just their card selections; it also entails interpreting their emotional & nonverbal cues while playing.
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