1.I have never met him before -> It........................................ 2.I have never eaten this kind of food before -> It is........................................................ 3.I've never seen this film before -> This............................................ 4.We've never drunk this kind of water before ->This is................................................. 5.He's never been to HCM city before ->It is.................................... 6.It is the first time I've seen this man ->I've ...................................... 7.This is the first time he phoned me ->He has........................................... 8.This is the first time I've talked to her ->I've.................................................. 9.This is the first time Nam has used computer ->Nam has....................................... 10.It is the first time Tom has sung ->Tom has................................................ 11.Ba had never listened to classical music before ->This was................................................. 12.Nam had never seen him before ->It was............................................. 13.I had never seen him before ->It was.................................................. 14.It was the first time Ba had killed chickens ->Ba had..................................................... 15.It was the first time she had eaten apple ->She had.................................................... 16.He last saw me a week ago ->He hasn't...................................... ->It is.................................................. 17.Ba stopped playing soccer when he was 30 ->Ba hasn't.................................................. 18.Hung began listening to music at 8 o'clock ->Hung has......................................... 19.He didn't smoke two years ago ->He hasn't............................................. ->It is..............................................