首脑会议宣言要求满足非洲的特殊需要，是正确和必要的。

The Declaration of the Summit calls for efforts to meet the special needs of Africa. I think this is correct and necessary.

youdao

而由各种神经诊断性检查发现的异常，往往是伴随性的，对此进行治疗可能是正确和必要的。 但却不能使病人症状获得改善。

Abnormalities that are noted on various neurodiagnostic studies are often incidental findings whose treatment may be justified and necessary but will not improve the patient's symptoms.

youdao

如果他们对互联网有更好的理解，他们就会看到确保他们的孩子正确和负责任地使用互联网的必要性。

If they had a better understanding of the Internet, they would see the need to make sure that their children use it properly and responsibly.

youdao