《国语·齐语·管仲对桓公以霸术》
让他返齐，必将会长久地成为鲁国的祸患。 
令彼在齐，则必长为鲁国忧矣。 
If we let him return to Qi, he will certainly become a long-lasting problem for the State of Lu.
<s>[INST] Convert the following modern Chinese text into Classical Chinese: 让他返齐，必将会长久地成为鲁国的祸患。  [/INST] 令彼在齐，则必长为鲁国忧矣。 </s>
Convert the following modern Chinese text into Classical Chinese: 让他返齐，必将会长久地成为鲁国的祸患。
user
令彼在齐，则必长为鲁国忧矣。
assistant