UNIX for Advanced & Expert Users

Hi,
Suppose I have a file with many lines as follows. Now I want to find the following questions from the file through shell script or commands.

Code:

My name is XYZ. XYZ works for GHT and XYZ is part of PES. GHT is a good organization. XYZ knows swimming. XYZ is also very keen in reading. XYZ is a very hardworking guy.

Now, (i) How many occurrences of XYZ are there?
(ii) Print lines where XYZ occurrence is more than 1.
(iii) Print lines which start with XYZ

(iv) Print lines which end with XYZ

(v) Print lines which doesn't have XYZ

Thanks for the inputs.

Moderator's Comments:

edit by bakunin: this is obviously homework and - as you should know from the rules you promised to read and accept - for homework special provisions apply. You have to post this at the Homework board, here it neither allowed to ask nor to answer. Don't make me tell you this a second time.

is this kind of homework ?

Yes it is. Scores a 0.998 on my built-in homeworkometer.

-closed-

bakunin