Confusion with the Course

I'm studying Rocket Japanese Premium Stage 1 I'm confused by some apparent anomalies in the course material. 1. In Lesson 3.9 it appears that the columns headers are reversed in the list of 1 verbs. Are they? 2. I can't find any explanation as to why the verbs are categorised as 1 and 5 dan, although I think I have read it somewhere. Any advice please? 3. In the audios the sounding for "masu" and "imasu" endings sometimes leave the "u" silent and sometimes it is pronounced. Why is this?

Yes, the columns are reversed there and I also had the problem with the display of the new Kanji character. I don't know a clear explanation why the categories of verbs are name like that, but I can explain a bit about the "u" sound. When pronouncing "su" the Japanese people tend to let the "u" sound down and pronounce an abrupt "s". This is in conversation only and they don't always do it, it depends from person to person on how they spell it. For example: suki is often pronounced like ski ("abrupt s"), or gozaimasu is often spelled as: gozaimas (again, an abrupt s as the last sound). Same goes with "shi". The "i" sound may not always be spelled clearly and the group is spelled like English "sh". Well I hope you get what I mean. Hope that helped, コッド

Yes that helps, thank you. It’s good to have confirmation that my senses aren’t deluding me. With the “u” sound I sometimes find it very natural to drop it but on other occasions it seems to allow the speech to flow better if it is sounded. Your explanation helps this.

どういたしまして

I find that leaving a brief "u" sound helps to let the sentence flow. I don't say su-ki, but at the same time I don't say "ski". I just doesn't sound right. I say something in between. I don't pronounce the "u" if it falls at the end of the sentence. About 1dan and 5dan verbs: 5dan verbs end in -au, -ou, -uu, -ku, -gu, -su, -tsu, -nu, -bu, -mu or -ru. 1dan verbs end in -iru or -eru. However not all verbs that end in -iru/eru are 1dan verbs. Eg. Hashiru (to run) is a 5dan verb. 5dan verbs conjugate after the consonant: Eg. Hashiru>hashir(u)>hashir(imasu) While 1dan verbs conjugate after the vowel: Eg. Miru>mi(ru)>mi(masu) or taberu>tabe(ru)>tabe(masu). That's the basics of it. The reason they're called 1dan and 5dan (lit. 1-row and 5-row) has something to do with the gojuuon table (the ordering of kana), but I can't remember exactly what. Derek-san! Please help!

@コッド. Your post seems to have dissapeared, so I don't know if you deleted it, but I received an email notification: It's actually -uu. Example of verbs are kuruu (to go mad), suu (to smoke) and sukuu (to save).

Yes, I deleted it because I realized that I was wrong :). Sorry for the confusion caused :D