Which room is your class in? Where is your class? my class is in room 101. Perhaps the most the typical role of prepositions is to Mark locative and temporal information in a language - that is, information concerning location and time. in English, propositions such as under, over, into, on (top of), beside, towards, in (front of) Mark location, while prepositions such as before, during, after, while, until and since Mark temporal information: before the meeting, during the war, until 4:00. Many prepositions Express either kind of meaning: after the game, After the traffic lights; over the bridge, over the summer. Prepositions also Express the manner in which an event is carried out: with a knife, by means of poison, in a loud voice, and so on. In terms of function, many PPS are optional modifiers of verbs, As in we left [before the meeting], She sang [in a loud voice] - a pps are in brackets.