〜てください

〜てください is the polite-register request — "please do X." 待ってください = "Please wait." It's the standard instruction form in classrooms, signs, and customer interactions: 静かにしてください, ここに座ってください.

The register is polite but not deferential — it's appropriate for teacher-to-student, doctor-to-patient, or speaker-to-stranger, but it can sound slightly commanding when used upward. For requests to superiors, soften further with 〜ていただけませんか or 〜ていただきたいんですが.

Dropping ください leaves the bare て-form, which in casual speech functions as an informal request: 待って — "wait." That's the form between close friends and family.

Negative request — "please don't do X" — is 〜ないでください: 心配しないでください — "Please don't worry." The negative form uses 〜ないで (the negative te-form variant), not 〜なくて.