彼がいきなり、アナウンサーのまねをしてしゃべり始めたので笑ってしまった。

he; him; his; boyfriend

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

abruptly; suddenly; all of a sudden; without warning

announcer

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

imitating; copying; mimicry; behavior; behaviour; action; conduct

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 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

to talk; to chat; to chatter

that being the case; because of ...; the reason is ....; given that...

to laugh; to smile; to sneer; to ridicule; to be dumbfounded; to be flabbergasted