Today (11/24) Today (11/24)

Today, I finished my tasks for my job, which made me very happy. Today, I finished my tasks for my job, which made me very happy.

I am guessing that there were multiple tasks. Also, the job is yours, and hence you should have "my" before it.

Today, I finished mya task for my job. Today, I finished a task for my job.

Today, I finished my task for the job. Today, I finished my task for the job.

OPTION A: Today, I finished myone task for jobat work. OPTION A: Today,I finished one work task . OPTION A: Today, I finished one task at work. OPTION A: Today,I finished one work task .

very happy!

"Very happy" is not a full sentence. Instead, you should add it to the previous sentence.

I'm very happy! I'm very happy!

In English, we can't omit the subject the way Japanese does.

I am very happy! I am very happy!

but,However, other tasks don't get finished because my boss can't finished giving tasks for mekeeps giving me work. However, other tasks don't get finished because my boss keeps giving me work.

Start each sentence with a capital letter. Also, instead of using "But" as the start of a sentence, it is better to use "However". Other than that, most of the sentence was correct grammatically, but didn't flow well.

bBut, my other tasks doaren't finished because my boss cahasn't finished giving those tasks forto me. But, my other tasks aren't finished because my boss hasn't finished giving those tasks to me.

bBut, other tasks don't finish because my boss can't finishedkeeps giving tasks forto me. But other tasks don't finish because my boss keeps giving tasks to me.

but,other tasks don't finish because my boss can't finished giving tasks for meHowever, I haven't finished other tasks because my boss keep piling new tasks on my desk. However, I haven't finished other tasks because my boss keep piling new tasks on my desk.

He didoesn't come to our workplace. He doesn't come to our workplace.

He didn't come to our workplace. He didn't come to our workplace.

He didn't come our workplaceToday, my boss didn't appear at work. Today, my boss didn't appear at work.

I don't know the reason why. I don't know the reason why.

I don't know the reason. (or: I don't know why) I don't know the reason. (or: I don't know why)

I don't know the reason. I don't know the reason.

OPTION A: I don't know the reason. OPTION B: The reason for that is unclear. OPTION A: I don't know the reason. OPTION B: The reason for that is unclear.