adjective, noun · truthful, sincere, and straightforward in speech and behavior

他是个老实人，从来不说谎。

adjective · easily deceived or lacking worldly experience; gullible

你太老实了，居然相信了他的鬼话。

adjective · following rules, staying out of trouble, or being disciplined

老师走后，同学们在教室里都很老实。