[masaegu]

Originally Posted by RobinMask

My textbook says that Regular I verbs change the final う sound into a える to create the potential. Whereas Regular II verbs change the final る into a られる.

I understand this rule pretty well and it's exceptions with irregular verbs, and in the excercise (changing verbs into their potential forms to create questions) I had very nearly full marks. Where I struggled was with two verbs: つくる and のる.

My textbook gave me as answers for these the potential forms of つくれます and のれます . . . my question is, why have they dropped the ら sound from these two verbs?

Never heard the terms "Regular I verbs" and "Regular II verbs" to be honest, but I am going to asume those are, respectively, "五段活用 verbs" and "一段活用 verbs" from what you are talking about.

If so, it is either your book teaches it wrong or you copied it wrong. Both つくる and のる are 五段活用 verbs and their potential forms are つくれます and のれます. There is absolutely no irregularity about these, either.　「ら」was not dropped. It never was in the potential forms of these verbs to begin with.

For 一段活用 verbs, however, there will be 「ら」 in the potential form unless we are discussing the modern-day らぬきことば, which is discussed in the thread:
http://www.japanforum.com/forum/japa...new-trend.html

To sum it up:

五段活用 verbs:
Dictionary form >> Potential form
作（つく）る　＞＞　作れる
乗（の）る　＞＞　乗れる
書（か）く　＞＞　書ける　
行（い）く　＞＞　行ける
遊（あそ）ぶ　＞＞　遊べる
読（よ）む　＞＞　読める

一段活用 verbs：
Dictionary form >> Potential form
食（た）べる　＞＞　食べられる
見（み）る　＞＞　見られる
寝（ね）る　＞＞　寝られる
着（き）る　＞＞　着られる
閉（と）じる　＞＞　閉じられる