お父さんはビールを全部飲んでしまいました。
- My father drank all the beer.

お父さんはビールを全部飲んでしまいました。 meaning: Dad drank all the beer.

The sentence follows a typical Japanese sentence structure: Subject - Topic - Object - Verb. ⚫︎ The subject is お父さん (Dad). ⚫︎ The topic marker は (wa) indicates the topic of the sentence. ⚫︎ The object is ビール (beer). ⚫︎ The object marker を (o) marks the direct object. ⚫︎ 全部 (zenbu) means "all". It modifies ビール (beer). ⚫︎ The verb phrase is 飲んでしまいました which is a past tense, and contains the verb 飲む(nomu) meaning to drink.

Particles are crucial in Japanese grammar as they indicate the grammatical function of words in a sentence. ⚫︎ は (wa): The topic marker. It indicates what the sentence is about. In this case, it's お父さん (Dad). ⚫︎ を (o): The direct object marker. It marks the noun that is directly affected by the verb. Here, it marks ビール (beer) as the thing being drunk.

This is a common grammar pattern indicating completion, regret, or that something has happened unexpectedly. It is formed by combining the -te form of a verb with the auxiliary verb しまう (shimau). ⚫︎ 飲む (nomu): to drink (dictionary form) ⚫︎ 飲んで (nonde): to drink (te-form) ⚫︎ 飲んでしまう (nonde shimau): to end up drinking / to drink completely ⚫︎ 飲んでしまいました (nonde shimaimashita): ended up drinking / drank completely (past tense) The past tense, ～てしまいました (～te shimaimashita), indicates that the action is finished. In this case, Dad finished drinking all the beer.

しまう (shimau) is an auxiliary verb that adds nuances of completion, regret, or that something has happened unexpectedly to the main verb. ⚫︎ In this sentence, it emphasizes that the beer was completely drunk. It also carries a slight nuance of "Oh no!" or that it wasn't necessarily intended.

全部 (zenbu) functions as an adverb, modifying the verb by telling us how much of something was done. ⚫︎ 全部 (zenbu) means "all" or "everything." It specifies that the entire quantity of the beer was drunk. This clarifies the extent of the action of drinking.