If ......

CONDITIONAL SENTENCES

 # Present situation  + possible #

If I have enough pocket money, I will buy a packet of «jumpers».
  (present simple)                            (future will)
 
I will buy a packet of «jumpers» if  I have enough pocket money.
   (future will)                                      (present simple)


# Present situation + hypothesis  #

If I had enough pocket money, I would buy a packet of «jumpers».
  (past simple)                            (conditional  would)
 
I would buy a packet of «jumpers» if  I had enough pocket money.
   (conditional would)                             (past simple)
 
[If I had enough money, but I haven't]


 
# Past situation + impossible  #

If I had had enough pocket money, I would have bought a packet of «jumpers».
  (past perfect)                                         (conditional perfect)
  
I would have bought a packet of «jumpers» if I had had enough pocket money.
     (conditional perfect)                                         (past perfect)