Verb forms and pronunciation

Hi: this is a third post, i was not very clear in the previous twos. i'm working on english verb conjugation, and i find a connection between pronunciation and conjugation, that is, the necessary change of the verb form before adding suffix is probably meant to meet the requirement of pronunciation, for example, if we didn't double the consonant of "p" in "drop", before adding -ed, we would lose the original pronunciation. And this rule or connection applies to some pattern of the verb forms, such as "panicking". But i'm not sure about the verb with a consonant plus "y" ending, such as "carry", "study". if we directly add -ed, or -s, does the original pronunciation would change? what would "carryed", or "carrys" be prouounced, according to your pronunciation habitude? (carryed and carrys don’t exist in English, and the correct ones are carried and carries, what I mean is a hypothetical situation in order to learn more.) as you must see, i'm not a native speaker.

Thank you very much, and i'm much appreciated for the previous answers. sorry for my English; hope i'm clear this time. and have a nice day.