Teaching certainly helps, provided you make a conscious effort to teach the right things.

My high school deskmate was terrible at French, and one day the teacher asked, how do you say Merry Christmas?

I suggested to my deskmate that you say Feliz Navidad. 😈

She was so excited to raise her hand and answer the question.

The teacher did not receive well her answer.

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How about handwriting texts from magazines or books in the language you're trying to learn?

My French teacher forced me to do this exercise while prepping for my high school final exams.

It's easier for your brain to remember them, and you unconsciously become more intuitive about integrating words into sentences.

You get a better feel for the phrase structure.