speak so thatให้ introduces the desired result or manner of speaking: “speak so that…” or “speak in a way that…”. It is commonly followed by an adjective or adverb such as ชัดเจน (clearly), ดัง (loudly), or ถูก (correctly).
TH: กรุณาพูดให้ช้าเพื่อให้ทุกคนเข้าใจ
EN: Please speak slowly so that everyone can understand.