Grammar Errors

What English problem/s do you have?

Give at least one.

The professor lectured the students took notes.

The alarm clock blared out persistently Eric finally leaped out of his bed.

The experiment was a success my group was happy with the results.

I haven’t not experienced cultivating plants before.

Health workers scarcely never receive enough compensation; hence their salary needs  to be raised.

Some students have not hardly had stable internet connection during the online setup.

Address a note to yourself on how you can improve your grammar skills.