it was necessary for him to go out last night

问题描述:

it was necessary for him to go out last night
it is necessary for me to have some help
she said it would be necessary for us to stay here

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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