Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Ex Input:
Context: Lake Forest High School Clubs Environmental Club Club members are provided opportunities to realize their goals of environmental service. The majority of projects are student-initiated. Last year's activities included: the LFHS Courtyard Garden upkeep, Bike to School Day with free cocoa and snacks, an "eat local" 100-mile dinner, recycling solutions for LFHS, beach cleanup through the Great Lakes Alliance, and Earth Week celebrations. Meetings: First Friday of the month in Room 5 at 7:00 a.m. Advisor: Ms Mary Beth Nawor, _ Peer Tutoring Students volunteer to help fellow students in improving their academic and organizational skills. Students tutor LFHS and middle school students on an individually scheduled basis. LFHS tutors must have proficiency in the academic area in which they wish to tutor, but middle school tutors only need general academic proficiency. Meetings: All tutoring is done on an individually scheduled basis. Advisor: Ms Kathy O'Hara, _ Young Idea Young Idea is LFHS's art and literary magazine. Students of all ages who love writing and art are encouraged to become part of the staff of this award-winning magazine. Young Idea encourages all students to submit art and literature works to the magazine, whether they are a part of the staff or not. From September to February, Young Idea meets on Thursdays after school in the Public Room to discuss the pieces that have been submitted to the magazine and provide feedback for the authors. Meetings: See above explanation. Advisor: Ms Debbie Zare, _ Scout Buddies Scout Buddies is a friendship club which helps build friendship among individuals with and without disabilities. Club members participate in a variety of social activities both within the school and in the community. Activities include organizing holiday parties in the school, bowling, going to the movies, and eating out in local restaurants. Meetings: Monthly meeting dates vary, but in Room 134. Advisor: Ms Donna Lovitsch, _ 
 Question: Which club provides help for students poor in study?

Ex Output:
peer tutoring.


Ex Input:
Context: A covalent bond is the force of attraction that holds together two atoms that share a pair of electrons. The shared electrons are attracted to the nuclei of both atoms. Covalent bonds form only between atoms of nonmetals. The two atoms may be the same or different elements. If the bonds form between atoms of different elements, a covalent compound forms. Covalent compounds are described in detail later in the lesson. To see a video about covalent bonding, go to this URL: (6:20). MEDIA Click image to the left or use the URL below. URL: Figure 7.7 shows an example of a covalent bond forming between two atoms of the same element, in this case two atoms of hydrogen. The two atoms share a pair of electrons. Hydrogen normally occurs in two-atom, or diatomic, molecules like this (di- means "two"). Several other elements also normally occur as diatomic molecules: nitrogen, oxygen, and all but one of the halogens (fluorine, chlorine, bromine, and iodine). Covalent bonds form because they give atoms a more stable arrangement of electrons. Look at the hydrogen atoms in Figure 7.7. Alone, each hydrogen atom has just one electron. By sharing electrons with another hydrogen atom, it has two electrons: its own and the one in the other hydrogen atom. The shared electrons are attracted to both hydrogen nuclei. This force of attraction holds the two atoms together as a molecule of hydrogen. Some atoms need to share more than one pair of electrons to have a full outer energy level. For example, an oxygen atom has six valence electrons. It needs two more electrons to fill its outer energy level. Therefore, it must form two covalent bonds. This can happen in many different ways. One way is shown in Figure 7.8. The oxygen atom in the figure has covalent bonds with two hydrogen atoms. This forms the covalent compound water. In some covalent bonds, electrons are not shared equally between the two atoms. These are called polar bonds. Figure 7.9 shows this for water. The oxygen atom attracts the shared electrons more strongly because its nucleus has more positively charged protons. As a result, the oxygen atom becomes slightly negative in charge. The hydrogen atoms attract the electrons less strongly. They become slightly positive in charge. For another example of polar bonds, see the video at this URL: (0:52). MEDIA Click image to the left or use the URL below. URL: In other covalent bonds, electrons are shared equally. These bonds are called nonpolar bonds. Neither atom attracts the shared electrons more strongly. As a result, the atoms remain neutral. Figure 7.10 shows an example of nonpolar bonds. Covalent bonds between atoms of different elements form covalent compounds. The smallest, simplest covalent compounds have molecules with just two atoms. An example is hydrogen chloride (HCl). It consists of one hydrogen atom and one chlorine atom. The largest, most complex covalent molecules have thousands of atoms. Examples include proteins and carbohydrates. These are compounds in living things. Helpful Hints Naming Covalent Compounds Follow these rules in naming simple covalent compounds: The element closer to the left of the periodic table is named first. The second element gets the suffix ide. Prefixes such as di- (2) and tri- (3) show the number of each atom in the compound. These are written with subscripts in the chemical formula. Example: The gas that consists of one carbon atom and two oxygen atoms is named carbon dioxide. Its chemical formula is CO2 . You Try It! Problem: What is the name of the compound that contains three oxygen atoms and two nitrogen atoms? What is its chemical formula? Covalent compounds have different properties than ionic compounds because of their bonds. Covalent compounds exist as individual molecules rather than crystals. It takes less energy for individual molecules than ions in a crystal to pull apart. As a result, covalent compounds have lower melting and boiling points than ionic compounds. Many are gases or liquids at room temperature. Covalent compounds have shared electrons. These are not free to move like the transferred electrons of ionic 
 Question: any compound consisting of two or more nonmetals

Ex Output:
covalent compound


Ex Input:
Context: In breast cancer the development of metastasis is a major turning point in the treatment and outcome of the disease. Throughout tumour development, and especially in the development of metastasis, epithelial mesenchymal transition takes place. During this transformation into a mesenchymal phenotype, the tumour cells undergo a series of structural changes. The loss of structural integrity and adoption of mesenchymal filaments enables cells to detach from the epithelial cell layer and metastasise. Keratins form the intermediate filaments of the cytoskeleton and provide scaffold structures within cells. During cancer progression the intermediate filaments are reorganised, and dramatic changes are seen in their protein components. Keratins K8, K18, K19 and vimentin are intermediate filament proteins with altered expression profiles during tumour development. We have used in vivo and in vitro models to analyse changes in intermediate filament proteins. Antibody-based methods were used to study K8 levels and proteomic analysis to profile the protein content of metastatic breast cancer cell variants. K8 expression declines as human breast tumours progress into an invasive phenotype. Analysis of IF proteins indicated altered expression profiles of K8, K18, K19 and vimentin, with K8, K18, K19 expressed in high levels in the T47D and MCF-7 cell lines, whereas the highly metastatic cell lines expressed lower levels of K8 and K18 and no detectable K19. Vimentin showed reverse expression profile with T47D and MCF-7 cells having no detectable vimentin expression whereas the highly metastatic MDA-MB-231 and MDA-MB-436 showed high levels. Analysis of acetylation status using specific antibodies suggested acetylation occurred within the central coiled domain in the MCF-7 and T47D cells. Inhibition of tumour growth by tissue factor (TF) shRNA resulted in a dramatic re-elevation of expression of K8 in xenographs of the highly metastatic MDA-MB-436 line. Intermediate filament expression alters during epithelial mesenchymal transition. Identified post translational modifications may play a role in alterations seen in the organisation, solubility and stability of these filaments. Epithelial mesenchymal transition can be reversed and an epithelial phenotype re-established. 
 Question: What are the structures formed when keratin molecules come together?

Ex Output:

intermediate filaments