how many conditional sentence types are possible?

Solution 1:

Last time I counted them, I found two hundred and seventy-seven English conditionals. There are of course others.

See this answer for details.

         I: If he will jump, you will not have to.
        II: If he will jump, he can win.
       III: If he will jump, he may win.
        IV: If he will jump, you must follow.
         V: If he will jump, you dare not follow.
        VI: If he will jump, you need not follow.

       VII: If he would escape, let him find help.
      VIII: If he would escape, he will find help.
        IX: If he would escape, he shall find help.
         X: If he would escape, he should find help.
        XI: If he would escape, he would find help.
       XII: If he would escape, he must find help.
      XIII: If he would escape, he can find help.
       XIV: If he would escape, he could find help.
        XV: If he would escape, he dare not find help.
       XVI: If he would escape, he need not find help.

      XVII: If he escapes, catch him.
     XVIII: If he escapes, you can catch him.
       XIX: If he escapes, you catch him.
        XX: If he escapes, you could catch him.
       XXI: If he escapes, you may catch him.
      XXII: If he escapes, you might catch him.
     XXIII: If he escapes, you must catch him.
      XXIV: If he escapes, you shall catch him.
       XXV: If he escapes, you should catch him.
      XXVI: If he escapes, you will catch him.
     XXVII: If he escapes, you would catch him.

    XXVIII: If he does escape, catch him.
      XXIX: If he does escape, you can catch him.
       XXX: If he does escape, you catch him.
      XXXI: If he does escape, you could catch him.
     XXXII: If he does escape, you may catch him.
    XXXIII: If he does escape, you might catch him.
     XXXIV: If he does escape, you must catch him.
      XXXV: If he does escape, you shall catch him.
     XXXVI: If he does escape, you should catch him.
    XXXVII: If he does escape, you will catch him.
   XXXVIII: If he does escape, you would catch him.

     XXXIX: If he should escape, catch him.
        XL: If he should escape, you can catch him.
       XLI: If he should escape, you catch him.
      XLII: If he should escape, you could catch him.
     XLIII: If he should escape, you may catch him.
      XLIV: If he should escape, you might catch him.
       XLV: If he should escape, you must catch him.
      XLVI: If he should escape, you shall catch him.
     XLVII: If he should escape, you should catch him.
    XLVIII: If he should escape, you will catch him.
      XLIX: If he should escape, you would catch him.

         L: If he escape, catch him.
        LI: If he escape, you can catch him.
       LII: If he escape, you catch him.
      LIII: If he escape, you could catch him.
       LIV: If he escape, you may catch him.
        LV: If he escape, you might catch him.
       LVI: If he escape, you must catch him.
      LVII: If he escape, you shall catch him.
     LVIII: If he escape, you should catch him.
       LIX: If he escape, you will catch him.
        LX: If he escape, you would catch him.

       LXI: If he dare escape, catch him.
      LXII: If he dare escape, you can catch him.
     LXIII: If he dare escape, you catch him.
      LXIV: If he dare escape, you could catch him.
       LXV: If he dare escape, you may catch him.
      LXVI: If he dare escape, you might catch him.
     LXVII: If he dare escape, you must catch him.
    LXVIII: If he dare escape, you shall catch him.
      LXIX: If he dare escape, you should catch him.
       LXX: If he dare escape, you will catch him.
      LXXI: If he dare escape, you would catch him.

     LXXII: Should he escape, catch him.
    LXXIII: Should he escape, you can catch him.
     LXXIV: Should he escape, you catch him.
      LXXV: Should he escape, you could catch him.
     LXXVI: Should he escape, you may catch him.
    LXXVII: Should he escape, you might catch him.
   LXXVIII: Should he escape, you must catch him.
     LXXIX: Should he escape, you shall catch him.
      LXXX: Should he escape, you should catch him.
     LXXXI: Should he escape, you will catch him.
    LXXXII: Should he escape, you would catch him.

   LXXXIII: Dare he escape, catch him.
    LXXXIV: Dare he escape, you can catch him.
     LXXXV: Dare he escape, you catch him.
    LXXXVI: Dare he escape, you could catch him.
   LXXXVII: Dare he escape, you may catch him.
  LXXXVIII: Dare he escape, you might catch him.
    LXXXIX: Dare he escape, you must catch him.
        XC: Dare he escape, you shall catch him.
       XCI: Dare he escape, you should catch him.
      XCII: Dare he escape, you will catch him.
     XCIII: Dare he escape, you would catch him.

      XCIV: If he has escaped, follow him.
       XCV: If he has escaped, he could fall.
      XCVI: If he has escaped, he dare not fail.
     XCVII: If he has escaped, he has fallen.
    XCVIII: If he has escaped, he may have fallen.
      XCIX: If he has escaped, he might fall.
         C: If he has escaped, he might have fallen.
        CI: If he has escaped, he must have fallen.
       CII: If he has escaped, he need not know.
      CIII: If he has escaped, he will have fallen.
       CIV: If he has escaped, he would fall.
        CV: If he has escaped, you can follow.
       CVI: If he has escaped, you could follow.
      CVII: If he has escaped, you may follow.
     CVIII: If he has escaped, you might follow.
       CIX: If he has escaped, you must follow.
        CX: If he has escaped, you shall follow.
       CXI: If he has escaped, you should follow.
      CXII: If he has escaped, you will follow.
     CXIII: If he has escaped, you would follow.

      CXIV: If he escaped, he fell.
       CXV: If he escaped, follow him.
      CXVI: If he escaped, he could fall.
     CXVII: If he escaped, he durst not fall.
    CXVIII: If he escaped, he has fallen.
      CXIX: If he escaped, he may have fallen.
       CXX: If he escaped, he might fall.
      CXXI: If he escaped, he might have fallen.
     CXXII: If he escaped, he must have fallen.
    CXXIII: If he escaped, he need not fall.
     CXXIV: If he escaped, he will have fallen.
      CXXV: If he escaped, he would have fallen.
     CXXVI: If he escaped, he would fall.
    CXXVII: If he escaped, you can follow.
   CXXVIII: If he escaped, you could follow.
     CXXIX: If he escaped, you may follow.
      CXXX: If he escaped, you might follow.
     CXXXI: If he escaped, you must follow.
    CXXXII: If he escaped, you shall follow.
   CXXXIII: If he escaped, you should follow.
    CXXXIV: If he escaped, you will follow.
     CXXXV: If he escaped, you would follow.

    CXXXVI: If he did escape, he fell.
   CXXXVII: If he did escape, follow him.
  CXXXVIII: If he did escape, he could fall.
    CXXXIX: If he did escape, he durst not fall.
       CXL: If he did escape, he has fallen.
      CXLI: If he did escape, he may have fallen.
     CXLII: If he did escape, he might fall.
    CXLIII: If he did escape, he might have fallen.
     CXLIV: If he did escape, he must have fallen.
      CXLV: If he did escape, he need not fall.
     CXLVI: If he did escape, he will have fallen.
    CXLVII: If he did escape, he would have fallen.
   CXLVIII: If he did escape, he would fall.
     CXLIX: If he did escape, you can follow.
        CL: If he did escape, you could follow.
       CLI: If he did escape, you may follow.
      CLII: If he did escape, you might follow.
     CLIII: If he did escape, you must follow.
      CLIV: If he did escape, you shall follow.
       CLV: If he did escape, you should follow.
      CLVI: If he did escape, you will follow.
     CLVII: If he did escape, you would follow.

    CLVIII: Did he escape, he fell.
      CLIX: Did he escape, follow him.
       CLX: Did he escape, he could fall.
      CLXI: Did he escape, he durst not fall.
     CLXII: Did he escape, he has fallen.
    CLXIII: Did he escape, he may have fallen.
     CLXIV: Did he escape, he might fall.
      CLXV: Did he escape, he might have fallen.
     CLXVI: Did he escape, he must have fallen.
    CLXVII: Did he escape, he need not fall.
   CLXVIII: Did he escape, he will have fallen.
     CLXIX: Did he escape, he would have fallen.
      CLXX: Did he escape, he would fall.
     CLXXI: Did he escape, you can follow.
    CLXXII: Did he escape, you could follow.
   CLXXIII: Did he escape, you may follow.
    CLXXIV: Did he escape, you might follow.
     CLXXV: Did he escape, you must follow.
    CLXXVI: Did he escape, you shall follow.
   CLXXVII: Did he escape, you should follow.
  CLXXVIII: Did he escape, you will follow.
    CLXXIX: Did he escape, you would follow.

     CLXXX: If he durst escape, he fell.
    CLXXXI: If he durst escape, follow him.
   CLXXXII: If he durst escape, he could fall.
  CLXXXIII: If he durst escape, he durst not fall.
   CLXXXIV: If he durst escape, he has fallen.
    CLXXXV: If he durst escape, he may have fallen.
   CLXXXVI: If he durst escape, he might fall.
  CLXXXVII: If he durst escape, he might have fallen.
 CLXXXVIII: If he durst escape, he must have fallen.
   CLXXXIX: If he durst escape, he need not fall.
       CXC: If he durst escape, he will have fallen.
      CXCI: If he durst escape, he would have fallen.
     CXCII: If he durst escape, he would fall.
    CXCIII: If he durst escape, you can follow.
     CXCIV: If he durst escape, you could follow.
      CXCV: If he durst escape, you may follow.
     CXCVI: If he durst escape, you might follow.
    CXCVII: If he durst escape, you must follow.
   CXCVIII: If he durst escape, you shall follow.
     CXCIX: If he durst escape, you should follow.
        CC: If he durst escape, you will follow.
       CCI: If he durst escape, you would follow.

      CCII: Durst he escape, he fell.
     CCIII: Durst he escape, follow him.
      CCIV: Durst he escape, he could fall.
       CCV: Durst he escape, he durst not fall.
      CCVI: Durst he escape, he has fallen.
     CCVII: Durst he escape, he may have fallen.
    CCVIII: Durst he escape, he might fall.
      CCIX: Durst he escape, he might have fallen.
       CCX: Durst he escape, he must have fallen.
      CCXI: Durst he escape, he need not fall.
     CCXII: Durst he escape, he will have fallen.
    CCXIII: Durst he escape, he would have fallen.
     CCXIV: Durst he escape, he would fall.
      CCXV: Durst he escape, you can follow.
     CCXVI: Durst he escape, you could follow.
    CCXVII: Durst he escape, you may follow.
   CCXVIII: Durst he escape, you might follow.
     CCXIX: Durst he escape, you must follow.
      CCXX: Durst he escape, you shall follow.
     CCXXI: Durst he escape, you should follow.
    CCXXII: Durst he escape, you will follow.
   CCXXIII: Durst he escape, you would follow.

    CCXXIV: If he had escaped, he could have known.
     CCXXV: If he had escaped, he might have known.
    CCXXVI: If he had escaped, he should have known.
   CCXXVII: If he had escaped, he would have known.

  CCXXVIII: Had he escaped, he could have known.
    CCXXIX: Had he escaped, he might have known.
     CCXXX: Had he escaped, he should have known.
    CCXXXI: Had he escaped, he would have known.

   CCXXXII: If he were to escape, he could fall.
  CCXXXIII: If he were to escape, he dare not fall.
   CCXXXIV: If he were to escape, he might fall.
    CCXXXV: If he were to escape, he must not fall.
   CCXXXVI: If he were to escape, he would fall.

  CCXXXVII: Were he to escape, he could fall.
 CCXXXVIII: Were he to escape, he dare not fall.
   CCXXXIX: Were he to escape, he might fall.
      CCXL: Were he to escape, he must not fall.
     CCXLI: Were he to escape, he would fall.

    CCXLII: If he can jump, he can escape.
   CCXLIII: If he can jump, he will escape.
    CCXLIV: If he can jump, he shall escape.
     CCXLV: If he can jump, he should escape.
    CCXLVI: If he can jump, he may escape.
   CCXLVII: If he can jump, he might escape.
  CCXLVIII: If he can jump, he must escape.

    CCXLIX: If he could jump, he escaped.
       CCL: If he could jump, he did escape.
      CCLI: If he could jump, he could escape.
     CCLII: If he could jump, he would escape.
    CCLIII: If he could jump, he might escape.
     CCLIV: If he could jump, he will have escaped.
      CCLV: If he could jump, he may have escaped.
     CCLVI: If he could jump, he must have escaped.
    CCLVII: If he could jump, he should have escaped.

   CCLVIII: If he might jump, he could escape.
     CCLIX: If he might jump, he would escape.
      CCLX: If he might jump, he might escape.

     CCLXI: If he will have jumped, he will have perished.
    CCLXII: If he might have jumped, you would have stopped him.
   CCLXIII: If he would have jumped, you would have had to catch him.
    CCLXIV: If he could have jumped, he would have done so.
     CCLXV: If he should have jumped, you would have had to catch him.

    CCLXVI: Might he have jumped, he would have stopped him.
   CCLXVII: Could he have jumped, he would have done so.
  CCLXVIII: Should he have jumped, you would have had to catch him.

    CCLXIX: But cut the wrong wire and he regrets it the rest of his life.
     CCLXX: But cut the wrong wire and he need not live to regret it.
    CCLXXI: But cut the wrong wire and he dare not live to regret it.
   CCLXXII: But cut the wrong wire and he will regret it the rest of his life.
  CCLXXIII: But cut the wrong wire and he would regret it the rest of his life.
   CCLXXIV: But cut the wrong wire and he shall regret it the rest of his life.
    CCLXXV: But cut the wrong wire and he should regret it the rest of his life.
   CCLXXVI: But cut the wrong wire and he may regret it the rest of his life.
  CCLXXVII: But cut the wrong wire and he might regret it the rest of his life.