如果直接引语是祈使句，变为间接引语时，要将祈使句的动词原形变为带to的不定式，并根据句子意思在不定式前加上tell/ask/order等动词，如果祈使句是否定句，在不定式前面还要加上not。例：
The hostess said to us, “Please sit down.”
→ The hostess asked us to sit down.
He said, “Don't make so much noise, boys.”
→ He told the boys not to make so much noise.