1)When someone breaks an agreement it means that he doesn't X in the agreement's conditionds. What's the apt term which should be used here (instead of X, ?stand?)

2) Suppose I give someone a work and I give him an assignment and the criterion is that only provided he completes the assignment he can work. If he doesn't complete the assinment it means he doesn't X the criterion(may I use "stand" here?)

1 2
#1-- possibly 'he doesn't adhere to the conditions'.
#2-- possibly 'he doesn't meet the criterion'.

'Stand' doesn't work, but there are likely other options for both sentences, Mav.
Dear Maverick88,

You may say «satisfy» the conditions or the criteria.

Kind regards, Emotion: smile

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And also:

For no. 1: '...comply with the agreement's conditions.'

Restatement of no. 2: 'Suppose in agreeing to offer someone a job ('work'), I first give the individual an assignment, with the single criterion that the assignment be completed. If he doesn't complete the assignment, I can say that he hasn't [fulfilled/met/satisfied] the criterion.'
Thank you all very very much Emotion: smile

For the first one: satisfy\adhere to\comply with the conditions; are there any other possible options?

Thanks again
There are other possibilities such as "meet-", "observe-" and "fulfil the conditions" but the ones already given are better in most circumstances.
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No 1. recognize, acknowledge (you would have to remove the word "in") To keep the word "in" in, you would have to use the word partake. Another word you could use is concur, but I am not sure whether "concur in" is correct, I would use 'concur with"

(Mr P. please?)

You could also use Conform to.

No 2 Is Meet
"To concur with" is usually used when you are agreeing with a person's ideas. It's very formal - even archaic.

"I concur with your thoughts entirely, old chap".
Eimai, I know......I picked it up from 'The Aviator" Emotion: smile
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