To go to great/all/any lengths
To try all the possible ways of achieving something, even if it means going beyond expected or accepted boundaries.
I am willing to do anything (to achieve something).
Some people go to great lengths to achieve their goals – Some people are willing to do anything to achieve their goals.
Snowed under
To have too much work.
To have a lot of work; buried (overwhelmed) with work.
I have been snowed under with work during the last two weeks – I have been buried under work for the last two weeks.
Take (something) lying down
To accept or suffer (something) without arguing, complaining or trying to avoid it – to accept something without protest; to let it pass without reacting.
I won't take this insult lying down. I shall see my lawyer immediately – I will not let this insult go unanswered. I will see my lawyer immediately.
Back to the drawing board
To start again from the very beginning and make new plans.
Starting over from scratch; from the beginning.
The teacher didn't like our project, so we need to go back to the drawing board – The teacher didn't like our project, so we need to start all over again.