Today I didn't go to the library because I woke up too late. Today I didn't go to the library because I woke up late.

Due to the upcoming exam, there wereThere have been lots of students there recently due to the upcoming exam. There have been lots of students there recently due to the upcoming exam.

Due to the upcoming exam, there werehave been a lots of students recently. Due to the upcoming exam, there have been a lot of students recently.

Due to the upcoming exams, there werehave been lots of students recently. Due to the upcoming exams, there have been lots of students recently.

I can only could study at home, but as I mentioned before, it is difficult for me to focus on while reading these books. I can only study at home, but as I mentioned before, it is difficult for me to focus on while reading these books.

I only could study at home, but as I mentioned before, it is difficult for me to focus on these books while I'm at home. I only could study at home, but as I mentioned before, it is difficult for me to focus on these books while I'm at home.

I tried soreally hard to finish today's study plan, however, I still left one item not doneunfinished. I tried really hard to finish today's study plan, however, I still left one item unfinished.

I tried so hard to finish today's study plan, however, I still lefthave one item notleft to be done. I tried so hard to finish today's study plan, however, I still have one item left to be done.

I rarely woake up as soon aswhen the alarm clock ringings. I rarely wake up when the alarm clock rings.

I rarely woake up [as soon as | when] the alarm clock rings / starts ringing. I rarely wake up [as soon as | when] the alarm clock rings / starts ringing.

I rarely woake up as soon as the alarm clock ringings. I rarely wake up as soon as the alarm clock rings.

I rarely woake up as soon as the alarm clock ringings. I rarely wake up as soon as the alarm clock rings.

I usually sleep in until 7:45 a.m., but today my alarm clock has started ringing at 6:45. I usually sleep in until 7:45 a.m., but today my alarm clock started ringing at 6:45.

As a result, I'm used to hitting the snooze button, s. Sometimes, I do it unconsciously. As a result, I'm used to hitting the snooze button. Sometimes I do it unconsciously.

As a result, I'm used to hitting the snooze button, sometimes, I do it unconsciously. As a result, I'm used to hitting the snooze button, sometimes unconsciously.

As a result, I'm used to hitting the snooze button, s. Sometimes, I do it unconsciously. As a result, I'm used to hitting the snooze button. Sometimes, I do it unconsciously.

This is better in two sentences.

I want to develop a habit of waking up early, yet it's hard for me, especially in the winter. I want to develop a habit of waking up early, yet it's hard for me, especially in the winter.

I want to develop a / the habit of waking up early, yet it's hard for me, especially in (the) winter. I want to develop a / the habit of waking up early, yet it's hard for me, especially in (the) winter.

I want to develop a habit of waking up early, yet it's hard for me, especially in the winter. I want to develop a habit of waking up early, yet it's hard for me, especially in the winter.