Hi! So, before I start on anything, I'd just like to make things clear that even though I may not be the best author out there, I have been a beta-reader on LiveJournal for a rather long time. I have read many different stories, and I can assure you that I hold rather high standards for the stories that I beta on. Very often, I've been told that my reviews and critics are extremely harsh and thus not many dare to pass me their stories for a read-through. I think that at the end of the day, all I had really wanted was for them to improve on their writing. 

Therefore, I've decided to start this up. In no way am I trying to flame any story or authors if there are coincidences.

Let's get real, how many of you have read stories which have such interesting storylines, but the language was disappointing? It was so poor to the extent that it required a great effort just to read a sentence? Especially for grammar nazis, a simple mistake would spoil the entire mood of the story. Getting to the first point:

-Grammar (Past & Present Tenses)

I understand that most of you are not able to read through your own stories, posting immediately right after writing them out (exactly what I do). However, it's definitely better to play safe by reading the paragraph as you type. This will reduce the chances of grammar errors. 

Nonetheless, the term Grammar, actually refers to a very broad and vague term of the English language.
I won't be exactly pin-pointing out a specific part, but I guess a problem which most authors who do not have a steady grasp of the language would run into would be the tenses and phrasing. Although, I have met people who have English as their first language who still mixes up their present and past tenses.

For an example:

'Suho reaches out for Kyungsoo, in hopes of being able to catch the other boy before he gets swarmed into the crowd. However, a sudden push from the back caused him to fell.'

In this case, 'reaches' is a present tense of 'reached', and 'swarmed' is the past of 'swarms'. In here, it goes well together as it is part of Suho's imagination, with him thinking of the near future when Kyungsoo gets drowned in the crowd. 
You notice that the word 'caused' is in italics. There is nothing wrong with using 'caused', as it is wrong to use the present tense 'cause'. When using 'caused' (past tense), 'had' should come before 'caused', otherwise, you should use 'causes' (on-going present tense). 
'Fell' is the past tense of 'fall'. 

The improvised version should be:

'Suho reaches out for Kyungsoo, in hopes of being able to catch the other boy before he gets swarmed into the crowd. However, a sudden push from the back had caused him to fall.'

The transition from present to past tense should never be awkward. I.e, 'However, a sudden push from the back causes him to fell.'. 
Do you see how awkward it is? At least make it, 'However, a sudden push from the back had caused him to fell.'

Basically tl;dr for you lazy asses: If you're going to make a past/present tense error, at least make it easier for the rest to skip through.

-Grammar [Connectors]

An important thing to note is the usage of word connectors. Words like 'and', 'but', 'as' and 'because' are sentence connectors.
They should never in any case be used to start a proper sentence unless it's needed. It is only used to start a sentence when authors need to build a specific kind of atmosphere, usually for a cliffhanger or to accumulate the tensed feeling within the audience.

I also write with a very simple theory: If you can't stand reading a part of your story, change it. To be honest, if the author isn't able to digest a single word of whatever they've written, and it isn't satisfactory to them, then it should be corrected till you get satisfaction.

Will touch more on the next few chapters. Have a good day :)
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