“Doesn’t” + Base Verb Correction

A common mistake in English is using “doesn’t” with a verb in the wrong form. For example, saying “He doesn’t knows” is incorrect because “doesn’t” already indicates the negative, so the main verb must stay in its base form.

Let’s correct it:
❌ No, he doesn’t knows.
✅ No, he doesn’t know.

Here are more correct examples:
• No, he doesn’t understand.
• No, he isn’t sure.

The rule is simple: after “doesn’t,” always use the base verb (without “s,” “ed,” or “ing”). Mastering this will help you sound more natural in English conversations. Keep practicing, and soon, it will feel automatic!