Which clause is an independent clause?

when i pass my classes

succeeding in my classes

how to succeed at school

success is passing all my classes

Which sentence uses the simple present tense of sleep? mr. ford sleeping on a feather mattress in his apartment. mr. ford will sleep on a feather mattress in his apartment. mr. ford sleeps on a feather mattress in his apartment. mr. ford slept on a feather mattress in his apartment.