it was necessary for him to go out last night

it is necessary for me to have some help ----- 对我来说有必要去寻求一些帮助
是it is + 形容词 + to do 的用法
she said it would be necessary for us to stay here---- 她说我们有必要留在这里
是it is + 形容词 + to do 在宾语从句中的用法,从句的时态跟着主句走,主句过去时,从句过去将来时

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