Sentences you can use'In my opnion'.
'As far as I know.'
'In my view.'
'I don't believe that.'
'I’m absolutely convinced that .'
'Yes, but on the other hand.'
'I see what you mean, but I think that’s not the whole story. '
'What I actually meant was.'
'The main problem is.'
'Above all we must keep in mind that.'
'I’m not convinced that.'
'Sorry to interrupt you, but.'
' Could you explain to me.'