How-to say “to begin to do VERB” (Pre-ます-Form VERB + かける)
The grammar pattern that consists of the Pre-ます-Form of a VERB word followed by the word かける expresses the idea of “beginning to do VERB.” This expression is very similar to another grammar pattern, Pre-ます-Form VERB + 始める, which also translates to “to begin VERBing.” The distinction between the two is that whereas Pre-ます-Form VERB + 始める more generally describes something that has begun doing a VERB action (and typically continues to do that action) , Pre-ます-Form VERB + かける a particular nuance of “on the verge of doing VERB, about to do VERB, almost do VERB, to get halfway into doing VERB, etc.” In a lot of cases, this nuance will also imply that the VERB action was halted after it was beginning to be done.
*かける is one of the rather special words in the Japanese language, wherein it can be associated with literally more than 20 different definitions, so do be careful about automatically assuming it is serving the function of this grammar pattern when you hear it being used!
Pre-ます-Form VERB + かける = “to start doing VERB”
Pre-ます-Form VERB + かけ + の + NOUN = “NOUN that SUBJECT had started doing VERB to/with”
(“Ah! I almost forgot!”)
Yomikakete iru hon wa kitai ni hanshite omoshirokunai.
(“The book that I’ve started reading isn’t as interesting as I had hoped.”)
Yomi kake no hon
(“Partly read book”)
Tabe kake no hamburger
Shukudai o shikaketa ga nokotta bubun wa sugoku muzukashii.
(“I started doing my homework, but the part that’s left is really hard.”)
Kare wa bo-tto shite, ochikaketa.
(“The guy was spacing out and nearly fell down.”)
Nekaketa ga totsuzen kasaikeihouki ga natta.
(“I was about to go to sleep but all of a sudden the fire alarm went off.”)