I have reviewed Kira's app in DMs before. I like Calvin's quirk, it can provide a lot of fun situations ingame with the marines. I've seen you in support duties where the marines were in some dire situations so I'm sure you'll do fine as synth.
While the questions brought up about tenses and english are not wrong, it's going over the top to deny an application because of that. As the others have said, writing a story is different from ingame dialogue. I have seen you talk ingame and I can completely understand you. One of the purposes of stories are to test if the player can write basic english capable enough for people to comprehend. Downvoting someone for making tense errors is honestly just looking for a reason to deny people.
I know you put a lot of effort in the application and observing you ingame, you have improved your roleplay and behavior.
+1 from me.