ようになる

ようになる is a fundamental pattern for describing personal growth, lifestyle changes, and shifts in state. While なる is used with nouns and adjectives (nouns and na-adjectives take になる, while i-adjectives take 〜くなる), ようになる is the standard construction for expressing change when using verbs.

Conjugation Rules:
ようになる only attaches to the plain non-past form of verbs (dictionary form or ない form). It never attaches to the past tense (た form). To show tense, なる conjugates like a standard U-verb to show past changes (e.g., ようになりました) or continuing states (e.g., ようになっています).

1. Change in Ability or State
When describing a new skill, dynamic verbs are used in the potential form (e.g., 'became able to swim'). Note that when using the potential form, the object particle を typically changes to が (e.g., 漢字を読む → 漢字が読めるようになる). For する verbs, use できる to show ability (e.g., 運転できるようになる). Non-volitional verbs, such as 分かる（わかる - to understand）or 見える（みえる - to be visible）, are used in their dictionary form to show a change in comprehension or perception. Note that continuous state verbs like ある and いる are generally not used with this pattern.

2. Change in Habit
When paired with the dictionary form of action verbs, it describes a new routine or recurring situation. For example, 'I've started drinking coffee every morning.' Time markers like 最近（さいきん - recently）or 〜てから (since doing) are frequently used to establish the timeline of the new habit. For する verbs, using する (e.g., 運転するようになる) expresses a change in habit rather than ability.

3. Negative Change
While you can use the negative form（〜ないようになる）to emphasize a gradual process, 〜なくなる (the adverbial form of the negative verb + なる) is the overwhelmingly standard way to express negative change for both habits and abilities (e.g., 飲まなくなる, 泳げなくなる).

4. Systemic Design
The form 〜ようになっている is often used to describe how a machine, system, or building is designed to function (e.g., 'this door is made to open automatically').

Key Nuance:
This pattern implies the change was a process or happened naturally. If you want to express a conscious effort, use ようにする. If you want to express that a change was decided by an external factor or rule, use ことになる instead of ようになる.