I saw her kiss him>>I saw her kissing him. He is said to have studied English for 10 years >> He said he had studied English for 10 years There was hardly any hope of his passing the exam >> It was hopeless for him to pass the exam or He could hardly have passed the exam I saw the house set fire >> I saw the burning house

They're all fine apart, from the third one. 'Set fire' is a transitive verb. For example, 'The burglars set fire to the house.' If, for example, you saw a spark from something land on a house and the house started to burn, you could say 'I saw the house catch fire.' For the first one, many native speakers would say ' of him passing..', which is less correct than your version. It is more correct to say 'of his passing..'.

They are all correct, except for the third one. You could say: I saw the house set on fire. or I saw the house catch on fire. or I saw the house be set on fire. The others are good-- in fact the first two are at a higher register of English than is used in every-day speech.

There was hardly any hope of him passing the exam. He is said to have studied English for 10 years. I saw the house being set on fire. I saw her kiss him.