Concern of KR verbs when conjugating with "~ 까요" From a Korean grammar book, it shows that when conjugating with "~ 까요" (meaning "is it fine whether ..."), it may take part in four different kind of verb groups: 1) verbs that contain NO consonant sound at the end before the infinitive ending 다 ( e.g. 하다 "to do" , 가다 "to go" ); 2) verbs that DO contain consonant sound at the end before the infinitive ending 다 ( e.g. 먹다 "to eat" , 읽다 "to read" ); 3) verbs that contain ㄹ consonant sound at the end before the infinitive ending 다 ( e.g. 살다 "to live" , 알다 "to know" ); 4) verbs that contain ㄷ consonant sound at the end before the infinitive ending 다 ( e.g. 듣다 "to hear" , 묻다 "to ask" ). The corresponding conjugations would be as follows: 1) to drop the infinitive ending ~다 and to add the ending ~까요 ; i.e., 하다 -- 하까요 , 가다 -- 가까요 ; 2) to drop the infinitive ending ~다 and to add the ending ~을까요 ; i.e., 먹다 -- 먹을까요 , 읽다 -- 읽을까요 ; 3) to drop the infinitive ending ~다 and to add the ending ~까요 ; i.e., 살다 -- 살까요 , 알다 -- 알까요 ; 4) to drop the infinitive ending ~다 and that ㄷ consonant sound, and to add the ending ~ㄹ을까요 ; i.e., 듣다 -- 들을까요 , 묻다 -- 물을까요 . However, within the list, I found a verb 받다 (meaning "to receive"), which theoretically should fall into the 4th group, but it falls instead into the 2nd group; and thus, 받다 -- 받을까요 (but NOT 발을까요)! Hence, I would like to ask, is there a systematical way that a Korean beginner may be able to distinguish such exceptions, or is it solely through memorization? In addition, are there other typical verbs (i.e., the ones which are broadly used) that may also fall into such exceptions?? Thank you very much for your kind attention and any precious answers and suggestions.