Nàge miǎntiǎn de nánhái mànmàn biàn de kāilǎng le.
That shy boy gradually became more outgoing.
Tips
usage
腼腆 suggests a gentle, endearing kind of shyness - not social anxiety or fear. It often carries a positive or neutral connotation. Compare with 害羞 (hàixiū), which is more general and can mean embarrassed or ashamed.
