Vocab

I think that 'slacken' is more common for physical uses, as in 'slacken the rope'.

Vctory OngBoth "slack" and "slacken" can be use as verbs to express a person be lazy and avoid work.
ex. Stop slacking and get on with that digging!
Could anybody tell me how to differentiate them ?
great thanks in advance!

Write "Many thanks in advance" instead of "Great thanks in advance."

Vctory Onggreat thanks in advance!

It should be "Many thanks in advance."

Write "Many thanks in advance" instead of "Great thanks in advance."

Actually, as a native speaker, I do not like the phrase at all in any form. It is presumptuous. It implies that someone must perform the service, and I often ignore such posts. A simple 'Please' at the beginning is sufficient, and then a 'Thank you' afterward IF and AFTER a useful response has b

Hi,

I have to add, sadly, that many people avoid the 'problem' by saying neither 'please' nor 'thank you' at all.

I often wonder if politeness is less valued in some other cultures.

Clive

Slack (verb) is most commonly used with "off" to mean to work less hard.
Someone who avoids work entirely is a "shirker".

"Slacken" is used mainly with muscles and ropes, and sometimes the wind. It means to make looser or more relaxed.

Here are some examples:

The rain will slack off after a while. Then we can go out.
We will win if we keep up the pace!

I agree with Clive. He has been reminding members to write "Please", but so far his request has fallen on deaf years. Many members ask questions as though it were the duty of other members to respond to their queries.