“Blood, sweat, and tears” is a lot of effort and suffering. Example: We put a lot of blood, sweat, and tears into fixing our old house.
"Meet halfway" means "to compromise". Example: You and Brian have been arguing about this for an hour! Can't you just meet halfway?
"Take something with a grain of salt" means "to not completely believe something…
"Beauty is in the eye of the beholder" means "different people have different opinions about what or who is beautiful". Example: It’s true that beauty is in the eye of the beholder. I haven’t found any of Mary’s boyfriends attractive.
“Forty winks” is a short sleep during the day. Example: He usually has forty winks going home on the train.