The infinitive is the base form of the verb, before the verb is conjugated. For example: to speak, to eat, to live are English verbs in the infinitive form; to + verb creates the infinitive of a verb in English. In Spanish the infinitives of verbs have three diferent endings: ar, er and ir.
Light dependent reactions produce ATP and NADPH from energy captured from light. Therefore without light it cannot proceed. Light independent reactions fix carbon dioxide into glucose using the ATP and NADPH produced in the light dependent reactions. So light independent reactions can occur without light as long as CO2, ATP and NADPH is present.
Hence in photosynthesis you have the light dependent reactions and the dark reactions while in respiration there is aerobic respiration and anaerobic respiration. In photosynthesis light dependent reactions, ultra violet light strikes chlorophyll pigments which excites electrons leading to separation of oxygen molecules from carbon dioxide. In the dark reactions, carbon molecules now independent of oxygen are converted into carbohydrates and stored in plant cells as energy and food source.