Lukman gives a good answer in the comment. If Lukman turns it into an answer, I will remove this answer.
``, `` respectively mean 'easy to' and 'difficult to'. Reason can vary depending on the context.
* It may be so because it tastes good/bad
* It may be at the right temperature or too hot/cold.
* It may be the right/wrong size to swallow
* It may be the right hardness or is too hard/soft
* It may be reasonable price or expensive
* ...