This coffee is hot to drink. Is it correct grammatically It can be without 'too'? 'This coffe is hot to drink' can i use this sentence?

Is 'He is disgusting to look at' correct grammatically? I think it is correct. But people say it is not common. He is awful to look at He is terrible to look at He is disgusting to look at Are three not common?

I saw the three books, the first of which i enjoyed. is this sentence correct? I think 'I saw the three books, i enjoyed the first of which' is more correct... And She thinks I am lying, which i do. Is it correct Also i think 'She thinks i am lying, i do which' is correct. Help me