ح - This is a flat 'H' in English, as in the words 'Have' 'Hamper' 'Harold',Depending on the accent of the speaker (some regional English variants clip the 'H' to say 'ave, 'amper, or 'Arold. Be clear when speaking that the H sound is not optional. خ - Usually written as 'KH' there is no direct English relation. The best attempts to teach this I have hear are to softly clear the back of the throat, as though a crumb of bread is stuck at the back of the throat. If the student is aware of other languages that use similar sounds (like the Welsh 'LL') it can be useful to ask them to approach it from that direction. I have heard English speakers continually try and fail to produce this sound, I have been told that it is even linked to their genetic language heritage how easily it comes to them. Some people just can't get their tongues round it!

I think its hard for foreign people to pronounce these two, how ever the closest sound would be 'haa' for ح and khaa for خ