[BASH] Contorl Terminal. and top utility.Help,Help

[ionguang]

Q1
I have written a bash script and a loop to display some output within a terminal and I using
tput cup 0 0 command to prevent the terminal scrolling(this is very important) before each complete output pattern.
The pattern refresh time by time but there is a question.
for example the loop produce its first pattern is:
Linux is better than Windows!
Linux is wonderful!
Have a good day!
and then the loop produce its second pattern which is(Thx you guys!):
The terminal will become like this:
Thx you guys!r than Windows!
Linux is wonderful!
Have a good day!

How can I fix that. What I really want it's only display the newer pattern which the loop produce and all the displaying should in the same terminal which will not scrolling.

I know there are something tput lines and tput cols
I consider to use them in such after each $ echo get the value that tput cols minus where the cols I am and produce some blank, but this sound

Q2
Can anyone get the script of the top utility, or What is the meaning of the some of the message produce by $ top
Cpu(s): 7.1%us, 3.1%sy, 0.0%ni, 89.6%id,

what's us sy ni id standfor? How can I get that.
My understanding is that
I can use $ ps aux to get the list.
but which user is categorize as us sy ni id ?
For my example I have root syslog 102 avahi 107 1000 ...... in the User cols



Thank you so much! Have a good day!

[ionguang]

For Q1
simply using tput ed after tput cup 0 0

Still need help with Q2

[RDU]

Q2.Cpu(s): 7.1%us, 3.1%sy, 0.0%ni, 89.6%id,

US = User space
SY = System (kernel)
NI = nice
ID = Idle

have a look at 'man top'', you can use a lot of cmd to sort results.