数+課
Needs a numeral in front of it and takes no だ/です, so there are no forms to conjugate.
課
kalessoncounter
Example sentences2
今日の宿題は三課までだよ。
kyou no shukudai wa san ka made da yo.
Today's homework goes up to lesson three. casual
この教科書には全部で十五課あります。
kono kyoukasho ni wa zenbu de juugo ka arimasu.
This textbook has fifteen lessons in total. neutral