Gerunds

SIMPLE
The teacher enjoys teaching.


PROGRESSIVE
Mr. Smith is really enjoying teaching his class.

PASSIVE
The students enjoy being taught.

PERFECT
The retired teacher recalled having taught.

PASSIVE + PROGRESSIVE.
The students are enjoying being taught by such an exciting new teacher.

PASSIVE + PERFECT
The older students recalled having been taught that already.


Reference:
http://www.englishpage.com/gerunds/part_3.htm