To take on more responsibilities than you can handle. For Example: If you took too big of a bite, you might have to spit some back out. If you take on too many responsibilities, you “bit off more than you could chew” and might have to go back on a previous committment.

Possessing certain qualities which are needed. For Example: if the manager of a basketball team is looking for a powerful player over 7 feet tall and is introduced to someone who meets those critera, he might say “this player fits the bill.”

Something that is perceived to be a sure thing or very likely to happen or result in success. For Example: a boss could say to another boss, “let’s have Daniel handle the reorganizing of this department, he’s a safe bet.”

In a situation where you’re not sure which side to take, you take the side most favorable to the other party. For Example: A woman could tell her friend, “I thought my boyfriend was cheating on me, but he insisted that he wasn’t so I gave him the benefit of the doubt and stopped worrying […]

Having lost one’s sanity, particularly as a result of drug or alcohol use. For Example: “His excessive drinking is starting to send him round the bend.”