If you reject something such as a proposal, a request, or an offer,
you do not accept it or you do not agree to it.
The British government is expected to reject the idea of
state subsidy for a new high speed railway...
If someone rejects another person who expects affection from them,
they are cold and unfriendly towards them.
...people who had been rejected by their lovers.
If you cannot afford something, you do not have enough money to pay for it.
My parents can't even afford a new refrigerator...
We couldn't afford to buy a new rug.