講義を聞いている時は、静かにしていなければならない。

lecture

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to hear; to listen (e.g. to music); to ask; to enquire; to query; to learn of; to hear about; to follow (advice); to comply with; to smell (esp. incense); to sample fragrance

time; hour; moment; occasion; case; chance; opportunity; season; the times; the age; the day; tense

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

quiet; silent; slow; unhurried; calm; peaceful

at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although

to do; to cause to become; to make (into); to turn (into); to serve as; to act as; to work as; to wear (clothes, a facial expression, etc.); to judge as being; to view as being; to think of as; to treat as; to use as; to decide on; to choose; to be sensed (of a smell, noise, etc.); to be (in a state, condition, etc.); to be worth; to cost; to pass (of time); to elapse; verbalizing suffix (applies to nouns noted in this dictionary with the part of speech "vs"); creates a humble verb (after a noun prefixed with "o" or "go"); to be just about to; to be just starting to; to try to; to attempt to