Here, the sentence provides enough context for the reader to realize that the dog is searching for his bone and was not successful in finding it. Therefore, it is the dog's "search" that is "fruitless" (ineffective). It would not make sense for his "hope," "desire," "appetite," or "bowl" to be fruitless.

Someone who is responsible for looking after someone else is called a “guardian.” A “champion” is someone who wins or has won something; a “competitor” is someone who takes part in a competition or someone who takes part in a game; an “actor” is someone who plays a role, like a movie star; and a “professor” is a teacher of college or university students.

Something that people have been doing for a long time is called a “tradition.” The word “supposition” is something you believe in but that there is no proof of; a “legend” is something from history that probably is not true but that people admire or like to talk about; a “conflict” is a fight; and “removal” means the act of taking something away.

The name given to arms and legs is "limbs." So, an arm is a “limb” and a leg is also a “limb.” To provide further help, a “notion” is an idea; “expressions” are sayings; a “hovel” is a shack or a small and messy house; and a “habitat” is an environment where something is meant to live, so a dolphin’s “habitat” is the ocean.

The condition of being very tired and exhausted is called “fatigue."

The context suggests that the correct answer is a place where “supporters,” or fans, go to watch a game. This means that the correct answer is “arena.” An “arena” is usually where a sports team plays. A “champion” is someone who has won a competition; a “triumph” is a great win; a “commentator” is someone who talks about what is going on during a sports game; and a “narrator” is someone in a story who is telling that story.

Because one of the students was rude to the other one, it makes sense that what began between them was some sort of fight or argument. This means the correct answer is “feud.” A “feud” is a long period of disagreement or dislike between two or more people. An “agreement” is a contract or shared plan. “Companionship” is the state of being around someone or friendship.

When you “honor” a group of people, it makes sense to do so in a “ceremony.” A "ceremony" is a formal or serious event to mark the importance of something or someone.

Something that is half one thing and half of another is said to be “hybrid.” The word “unique” means being the only example of something. Someone who is “responsible” can look after themselves and can be trusted to do the right things. “Wishful” means dreaming about something you want to happen, and “competitive” means taking a game or conflict seriously.

The use of the word "classmates" after the semicolon tells you that the underlined word must mean something very similar to "classmates." The word “peers” means classmates or people who are in your group. To provide additional help, "allies" are friends or people who are on your side.