I thought I had best have your opinion first.我认为最好先听听你的意见.You had best go with him.你最好是跟他去.He had best have done so.他这样做了就最好了....

应当，最好...

had best的音标：had best的英式发音音标为：[hæd best]had best的美式发音音标为：[hæd bɛst]...