1）當(dāng)let后只有一個(gè)單音節(jié)動(dòng)詞，變被動(dòng)語(yǔ)態(tài)時(shí)，可用不帶to 的不定式。
　　 they let the strange go.---> the strange was let go.
　
　2） 若let 后賓補(bǔ)較長(zhǎng)時(shí)，let 通常不用被動(dòng)語(yǔ)態(tài)，而用allow或permit 代替。
　　the nurse let me go to see my classmate in the hospital.
　　----> i was allowed / permitted to see my classmate in the hospital.