We can walk and ride a bike when I go to school.

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Is this sentence grammatical? When we grade this short sentence in terms of grammar, can this sentence get A? Or is it totally wrong?

Why did you change from "We" to "I"? The shift from plural to singular doesn't make sense.

The sentence "We can walk and ride a bike when I go to school" is grammatically correct. Here's how we can break it down:

1. Subject: "We" - This indicates that the speaker is referring to themselves and perhaps others.
2. Modal verb: "can" - This shows the ability or possibility to perform the action that follows.
3. Verb phrases: "walk" and "ride a bike" - These are the actions that the subject can do.
4. Time phrase: "when I go to school" - This indicates the specific time or condition in which the actions can be performed.

When we assess the grammaticality of a sentence, there isn't a grading system like A, B, or C, but rather the focus is on whether the sentence follows the rules and structure of the language. In this case, the sentence follows the basic sentence structure correctly and doesn't contain any obvious errors, so it can be considered grammatically correct. However, it's worth noting that the correctness of a sentence depends on the context in which it's used and the intended meaning.