ようになる

1. 1With a potential verb, it means coming to be able to do something you could not do before.Ex. 1
2. 2With a plain verb, it means starting to do something as a habit, or a situation changing into a new state.

Neutral in register and common in both speech and writing. It is often used in the past form ようになった to describe a change that has taken place over time, such as a new skill gained through practice or a changed daily routine. Unlike ようにする, which describes a conscious effort to do something, ようになる describes the resulting change itself.

• ようにするN4「ようにする」focuses on consciously taking care, making an effort, or taking measures to do (or try not to do) something; 「ようになる」focuses on the result of a change in ability or habit, without emphasizing volition. The two have different meanings and cannot be interchanged.
• ことになるN4「ことになる」expresses a decision or arrangement made by others, an organization, or objective circumstances, or a calculated result, often reported as 「ことになりました」; 「ようになる」expresses a change in ability or habit. The two cannot be interchanged.
• ことにするN4「ようになる」is a gradual change in ability or habit and does not emphasize volition; 「ことにする」is the subject's active decision, and also has the meaning of 'treat as / decide to regard as'. 「走るようになった」≠「走ることにした」, so they cannot be interchanged.
• つつあるN2「つつある」attaches to the masu-stem and only to verbs of change, emphasizing that a change is gradually progressing and not yet complete, mainly in written language such as news and academic papers; 「ようになる」focuses on the result after the change, so the two should not be casually interchanged.
• 一方だN3「一方だ」does not express gaining a new ability or habit, but emphasizes a change continuously developing in one direction, mostly for negative trends; it attaches only to the dictionary form of change verbs like 「増える」and is not used in the past tense, so the two cannot be interchanged.
• てくるN4「てくる」attaches to the te-form of a verb and is similar to 「ようになる」only when expressing change, emphasizing a change gradually progressing up to the reference point, as in 「上手になってきた」; it can also mean going somewhere and coming back, or coming toward the speaker. The two can be used together.

ようになる describes the resulting change in ability or habit, whether it came through deliberate effort such as practice or on its own. In contrast, ようにする describes the effort made toward a goal, ことにする a decision made by the speaker, and ことになる an outcome decided by others or by circumstances. Compared with てくる (a gradual change continuing up to now), つつある (a change currently in progress, more formal), and 一方だ (a trend moving steadily in one direction, often a negative one), ようになる focuses on arriving at a new ability or state.