Expressions

Never look a gift horse in the mouth: “a caballo regalado no le mires el diente"
To be there with the bells on (AmE) : to do something eagerly
The more, the merrier: an occasion will be more enjoyable with lots of people there
An apple a day keeps the doctor away
To be tangled up in something: to be involved in something
To keep oneself to oneself: not to share your feelings, emotions, interests, ideas...
To be there through thick and thin: to be there for somebody when there is a bad and a good situation
However alien it may seem: "por muy raro que parezca"
To get to grips with: to begin to understand or deal with (something, such as a problem) in a direct or effective way
To find the truth unpalatable: the reality, the fact is unpleasant and we don't like to know it.
As quick as a flash: very very quickly
"Better the devil you know...": it is better to have something bad but you already know, than something new that may be even worse
To bite your tongue: to make an effort not to say something
To be sick/green with envy: to be very unhappy because someone has something that you want
To rely on someone as the breadwinner: breadwinner is the person who brings the income to a family house. So, it means that the family trust in that person to do so.
To do something behind's somebody's back: to do something without that person knowing
Pull the other one!: ¡Anda ya!
There is a lot to be said for...: to indicate that something has advantages which deserve to be considered when someone is thinking about what to do
The lion's share: the big part
Cheer up!: ¡Animate!
Keep your hair on!: Calm down, relax
Love is blind: el amor es ciego
Beauty is in the eye of the beholder: la belleza está en el ojo de quien mira
To wear your heart on your sleeve: show your feelings openly
To live on a labourer's wage: A living wage is defined as the minimum income necessary for a worker to meet their basic needs. ...
To get something out of the way: to finish doing something, especially something difficult or unpleasant
To weight something up: to think carefully about the advantages or disadvantages of a situation before making a decision
To get rid of: to remove something that you do not want any longer:
To live it up: spend one's time in an extremely enjoyable way, typically by being extravagant or engaging in an exciting social life.
To be long in the tooth: (quite rude) to be old (a person)