<b>Is this sentence correct? Do I put "pay or paid" and why please? thank you very much<br/><br/>or do I put "paid" because of the "have" + past particple.</b><br/><br/><i>The reason we have to pay is to help support the teachers.<br/><br/>I have an appointment at 10 am.</i> <b>Do I put "ed" on "appointment" because of "have"</b>