1. Exercise regularly, and you will get taller.

2. Exercise regularly, and you will become taller.

3. Exercise regularly, and you will grow taller.
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Which ones are popular? Which ones are less common? Are they all grammatical?

All

three are correct.

All three sentences are grammatically correct and convey the same meaning. However, there are some subtle differences in the phrasing that may influence their popularity or usage.

1. "Exercise regularly, and you will get taller."
This sentence is straightforward and commonly used. It implies that consistent exercise has the potential to increase one's height.

2. "Exercise regularly, and you will become taller."
This sentence is also frequently used, but it emphasizes a more gradual transformation. The use of "become" suggests a process that may take time to achieve noticeable results.

3. "Exercise regularly, and you will grow taller."
This sentence is less common in everyday speech but is still grammatically correct. It relies on the verb "grow" to describe the increase in height, which implies a natural or organic development.

Overall, sentence 1 and 2 are more commonly used than sentence 3.