今日を限りにタバコをやめます。
- I will quit smoking as of today.

今日を限りにタバコをやめます。 meaning: I will quit smoking from today onwards.

The sentence follows a typical Japanese sentence structure, which is Subject-Object-Verb (SOV) order, although the subject is often omitted if it's clear from the context. ⚫︎ The subject, "I" (私 - *watashi*) is implied and not explicitly stated in this sentence. ⚫︎ The object, "smoking" (*tabako*) is implied. ⚫︎ The verb, "to quit" (*yamemasu*) is at the end. ⚫︎ The phrase 今日を限りに acts as an adverbial phrase, modifying the verb and indicating the time frame "from today onwards."

This pattern, 〜を限りに (*~o kagiri ni*), is a fixed expression indicating "starting from," "from now on," or "limited to." ⚫︎ It implies a boundary or a turning point, signaling a change or a specific timeframe. ⚫︎ This pattern can be used with time expressions, as in this sentence, or with other nouns to denote limits. ⚫︎ The particle に (*ni*) functions as a location marker. ⚫︎ 限り (*kagiri*) means "limit" or "boundary". ⚫︎ Example: 今年を限りに、このプロジェクトから退きます。 (*Kotoshi o kagiri ni, kono purojekuto kara shimasu.*) - "Starting from this year, I will withdraw from this project."

The particle に (*ni*) has multiple functions. ⚫︎ In this sentence, it functions as a location marker and indicates the scope or limitation. ⚫︎ It connects 限りに to the preceding noun 今日 (*kyou* - today). ⚫︎ It specifies the point in time from which the action will commence. ⚫︎ Another common use: 公園に子供がいます(*Kouen ni kodomo ga imasu*) - "There are children in the park". ⚫︎ Another common use: 私は来週日本に行きます(*Watashi wa raishuu Nihon ni ikimasu*) - "I will go to Japan next week".

The verb やめます (*yamemasu*) is the polite form (ます-form) of the verb やめる (*yameru*), which means "to quit," "to stop," or "to give up." ⚫︎ The base form is やめる (*yameru*). ⚫︎ The て-form is やめて (*yamete*). ⚫︎ The past tense (plain) is やめた (*yameta*). ⚫︎ The past tense (polite) is やめました (*yamemashita*). ⚫︎ The negative form (plain) is やめない (*yamenai*). ⚫︎ The negative form (polite) is やめません (*yamemasen*).

There are no explicit auxiliary verbs in this sentence. However, the verb やめます (*yamemasu*) itself is conjugated to express the future intention or a decision that has been made. ⚫︎ The sentence implies the speaker's future action of quitting smoking. ⚫︎ The meaning is clear due to the usage of the present polite form, which indicates a future action or a decision to do something. ⚫︎ The phrase を限りに sets the temporal limit, which helps understanding the nuance of the sentence, of an action that will start from that time.