The Perfect Participle (active)

The perfect participle can be used instead of the present participle in sentences  like the one below (i.e. where one action is immediately followed by another with the same subject):

• Tying one end of the rope to the wardrobe, Mike threw the other end out of thewindow  = Having tied one end of the rope to the wardrobe, Mike threw the other end out of the window.

The perfect participle emphasizes that the first action is complete before the second one starts, but is not normally necessary in combinations of this kind, except when the use of the present participle might lead to confusion.

• Reading the instructions, he snatched up the fire extinguisher

The above sentence might give the impression that the two actions were simultaneous. Here, therefore, the perfect participle would be better:

• Having read the instructions, he snatched up the fire extinguisher.

The perfect participle is, however, necessary when there is an interval of time between the two actions:

• Having failed twice, he didn't want to try again.

It is also used when the first action covered a period of time:

• Having been his own boss for such a long time, he found it hard to accept orders from another.