Would you explain about something below?<br/><br/>Are these dialog grammatical?<br/>Can I use both about and on in the sentences?<br/><br/>a: What do you lecture <u><b>about</b></u>?<br/>b: I lecture <u><b>about</b></u> English.<br/><br/>A: What do you lecture <u><b>on</b></u>?<br/>B: I lecture on English.